kernel_optimize_test/tools/perf/scripts/python/export-to-postgresql.py
Adrian Hunter 640432e6be perf scripts python: export-to-postgresql.py: Fix struct.pack() int argument
Python 3.8 is requiring that arguments being packed as integers are also
integers.  Add int() accordingly.

 Before:

   $ perf record -e intel_pt//u uname
   $ perf script --itrace=bep -s ~/libexec/perf-core/scripts/python/export-to-postgresql.py perf_data_db branches calls
   2020-06-25 16:09:10.547256 Creating database...
   2020-06-25 16:09:10.733185 Writing to intermediate files...
   Traceback (most recent call last):
     File "/home/ahunter/libexec/perf-core/scripts/python/export-to-postgresql.py", line 1106, in synth_data
       cbr(id, raw_buf)
     File "/home/ahunter/libexec/perf-core/scripts/python/export-to-postgresql.py", line 1058, in cbr
       value = struct.pack("!hiqiiiiii", 4, 8, id, 4, cbr, 4, MHz, 4, percent)
   struct.error: required argument is not an integer
   Fatal Python error: problem in Python trace event handler
   Python runtime state: initialized

   Current thread 0x00007f35d3695780 (most recent call first):
   <no Python frame>
   Aborted (core dumped)

 After:

   $ dropdb perf_data_db
   $ rm -rf perf_data_db-perf-data
   $ perf script --itrace=bep -s ~/libexec/perf-core/scripts/python/export-to-postgresql.py perf_data_db branches calls
   2020-06-25 16:09:40.990267 Creating database...
   2020-06-25 16:09:41.207009 Writing to intermediate files...
   2020-06-25 16:09:41.270915 Copying to database...
   2020-06-25 16:09:41.382030 Removing intermediate files...
   2020-06-25 16:09:41.384630 Adding primary keys
   2020-06-25 16:09:41.541894 Adding foreign keys
   2020-06-25 16:09:41.677044 Dropping unused tables
   2020-06-25 16:09:41.703761 Done

Fixes: aba44287a2 ("perf scripts python: export-to-postgresql.py: Export Intel PT power and ptwrite events")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200629091955.17090-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-07-03 08:15:02 -03:00

1112 lines
39 KiB
Python

# export-to-postgresql.py: export perf data to a postgresql database
# Copyright (c) 2014, Intel Corporation.
#
# This program is free software; you can redistribute it and/or modify it
# under the terms and conditions of the GNU General Public License,
# version 2, as published by the Free Software Foundation.
#
# This program is distributed in the hope it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
# more details.
from __future__ import print_function
import os
import sys
import struct
import datetime
# To use this script you will need to have installed package python-pyside which
# provides LGPL-licensed Python bindings for Qt. You will also need the package
# libqt4-sql-psql for Qt postgresql support.
#
# The script assumes postgresql is running on the local machine and that the
# user has postgresql permissions to create databases. Examples of installing
# postgresql and adding such a user are:
#
# fedora:
#
# $ sudo yum install postgresql postgresql-server qt-postgresql
# $ sudo su - postgres -c initdb
# $ sudo service postgresql start
# $ sudo su - postgres
# $ createuser -s <your user id here> # Older versions may not support -s, in which case answer the prompt below:
# Shall the new role be a superuser? (y/n) y
# $ sudo yum install python-pyside
#
# Alternately, to use Python3 and/or pyside 2, one of the following:
# $ sudo yum install python3-pyside
# $ pip install --user PySide2
# $ pip3 install --user PySide2
#
# ubuntu:
#
# $ sudo apt-get install postgresql
# $ sudo su - postgres
# $ createuser -s <your user id here>
# $ sudo apt-get install python-pyside.qtsql libqt4-sql-psql
#
# Alternately, to use Python3 and/or pyside 2, one of the following:
#
# $ sudo apt-get install python3-pyside.qtsql libqt4-sql-psql
# $ sudo apt-get install python-pyside2.qtsql libqt5sql5-psql
# $ sudo apt-get install python3-pyside2.qtsql libqt5sql5-psql
#
# An example of using this script with Intel PT:
#
# $ perf record -e intel_pt//u ls
# $ perf script -s ~/libexec/perf-core/scripts/python/export-to-postgresql.py pt_example branches calls
# 2015-05-29 12:49:23.464364 Creating database...
# 2015-05-29 12:49:26.281717 Writing to intermediate files...
# 2015-05-29 12:49:27.190383 Copying to database...
# 2015-05-29 12:49:28.140451 Removing intermediate files...
# 2015-05-29 12:49:28.147451 Adding primary keys
# 2015-05-29 12:49:28.655683 Adding foreign keys
# 2015-05-29 12:49:29.365350 Done
#
# To browse the database, psql can be used e.g.
#
# $ psql pt_example
# pt_example=# select * from samples_view where id < 100;
# pt_example=# \d+
# pt_example=# \d+ samples_view
# pt_example=# \q
#
# An example of using the database is provided by the script
# exported-sql-viewer.py. Refer to that script for details.
#
# Tables:
#
# The tables largely correspond to perf tools' data structures. They are largely self-explanatory.
#
# samples
#
# 'samples' is the main table. It represents what instruction was executing at a point in time
# when something (a selected event) happened. The memory address is the instruction pointer or 'ip'.
#
# calls
#
# 'calls' represents function calls and is related to 'samples' by 'call_id' and 'return_id'.
# 'calls' is only created when the 'calls' option to this script is specified.
#
# call_paths
#
# 'call_paths' represents all the call stacks. Each 'call' has an associated record in 'call_paths'.
# 'calls_paths' is only created when the 'calls' option to this script is specified.
#
# branch_types
#
# 'branch_types' provides descriptions for each type of branch.
#
# comm_threads
#
# 'comm_threads' shows how 'comms' relates to 'threads'.
#
# comms
#
# 'comms' contains a record for each 'comm' - the name given to the executable that is running.
#
# dsos
#
# 'dsos' contains a record for each executable file or library.
#
# machines
#
# 'machines' can be used to distinguish virtual machines if virtualization is supported.
#
# selected_events
#
# 'selected_events' contains a record for each kind of event that has been sampled.
#
# symbols
#
# 'symbols' contains a record for each symbol. Only symbols that have samples are present.
#
# threads
#
# 'threads' contains a record for each thread.
#
# Views:
#
# Most of the tables have views for more friendly display. The views are:
#
# calls_view
# call_paths_view
# comm_threads_view
# dsos_view
# machines_view
# samples_view
# symbols_view
# threads_view
#
# More examples of browsing the database with psql:
# Note that some of the examples are not the most optimal SQL query.
# Note that call information is only available if the script's 'calls' option has been used.
#
# Top 10 function calls (not aggregated by symbol):
#
# SELECT * FROM calls_view ORDER BY elapsed_time DESC LIMIT 10;
#
# Top 10 function calls (aggregated by symbol):
#
# SELECT symbol_id,(SELECT name FROM symbols WHERE id = symbol_id) AS symbol,
# SUM(elapsed_time) AS tot_elapsed_time,SUM(branch_count) AS tot_branch_count
# FROM calls_view GROUP BY symbol_id ORDER BY tot_elapsed_time DESC LIMIT 10;
#
# Note that the branch count gives a rough estimation of cpu usage, so functions
# that took a long time but have a relatively low branch count must have spent time
# waiting.
#
# Find symbols by pattern matching on part of the name (e.g. names containing 'alloc'):
#
# SELECT * FROM symbols_view WHERE name LIKE '%alloc%';
#
# Top 10 function calls for a specific symbol (e.g. whose symbol_id is 187):
#
# SELECT * FROM calls_view WHERE symbol_id = 187 ORDER BY elapsed_time DESC LIMIT 10;
#
# Show function calls made by function in the same context (i.e. same call path) (e.g. one with call_path_id 254):
#
# SELECT * FROM calls_view WHERE parent_call_path_id = 254;
#
# Show branches made during a function call (e.g. where call_id is 29357 and return_id is 29370 and tid is 29670)
#
# SELECT * FROM samples_view WHERE id >= 29357 AND id <= 29370 AND tid = 29670 AND event LIKE 'branches%';
#
# Show transactions:
#
# SELECT * FROM samples_view WHERE event = 'transactions';
#
# Note transaction start has 'in_tx' true whereas, transaction end has 'in_tx' false.
# Transaction aborts have branch_type_name 'transaction abort'
#
# Show transaction aborts:
#
# SELECT * FROM samples_view WHERE event = 'transactions' AND branch_type_name = 'transaction abort';
#
# To print a call stack requires walking the call_paths table. For example this python script:
# #!/usr/bin/python2
#
# import sys
# from PySide.QtSql import *
#
# if __name__ == '__main__':
# if (len(sys.argv) < 3):
# print >> sys.stderr, "Usage is: printcallstack.py <database name> <call_path_id>"
# raise Exception("Too few arguments")
# dbname = sys.argv[1]
# call_path_id = sys.argv[2]
# db = QSqlDatabase.addDatabase('QPSQL')
# db.setDatabaseName(dbname)
# if not db.open():
# raise Exception("Failed to open database " + dbname + " error: " + db.lastError().text())
# query = QSqlQuery(db)
# print " id ip symbol_id symbol dso_id dso_short_name"
# while call_path_id != 0 and call_path_id != 1:
# ret = query.exec_('SELECT * FROM call_paths_view WHERE id = ' + str(call_path_id))
# if not ret:
# raise Exception("Query failed: " + query.lastError().text())
# if not query.next():
# raise Exception("Query failed")
# print "{0:>6} {1:>10} {2:>9} {3:<30} {4:>6} {5:<30}".format(query.value(0), query.value(1), query.value(2), query.value(3), query.value(4), query.value(5))
# call_path_id = query.value(6)
pyside_version_1 = True
if not "pyside-version-1" in sys.argv:
try:
from PySide2.QtSql import *
pyside_version_1 = False
except:
pass
if pyside_version_1:
from PySide.QtSql import *
if sys.version_info < (3, 0):
def toserverstr(str):
return str
def toclientstr(str):
return str
else:
# Assume UTF-8 server_encoding and client_encoding
def toserverstr(str):
return bytes(str, "UTF_8")
def toclientstr(str):
return bytes(str, "UTF_8")
# Need to access PostgreSQL C library directly to use COPY FROM STDIN
from ctypes import *
libpq = CDLL("libpq.so.5")
PQconnectdb = libpq.PQconnectdb
PQconnectdb.restype = c_void_p
PQconnectdb.argtypes = [ c_char_p ]
PQfinish = libpq.PQfinish
PQfinish.argtypes = [ c_void_p ]
PQstatus = libpq.PQstatus
PQstatus.restype = c_int
PQstatus.argtypes = [ c_void_p ]
PQexec = libpq.PQexec
PQexec.restype = c_void_p
PQexec.argtypes = [ c_void_p, c_char_p ]
PQresultStatus = libpq.PQresultStatus
PQresultStatus.restype = c_int
PQresultStatus.argtypes = [ c_void_p ]
PQputCopyData = libpq.PQputCopyData
PQputCopyData.restype = c_int
PQputCopyData.argtypes = [ c_void_p, c_void_p, c_int ]
PQputCopyEnd = libpq.PQputCopyEnd
PQputCopyEnd.restype = c_int
PQputCopyEnd.argtypes = [ c_void_p, c_void_p ]
sys.path.append(os.environ['PERF_EXEC_PATH'] + \
'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')
# These perf imports are not used at present
#from perf_trace_context import *
#from Core import *
perf_db_export_mode = True
perf_db_export_calls = False
perf_db_export_callchains = False
def printerr(*args, **kw_args):
print(*args, file=sys.stderr, **kw_args)
def printdate(*args, **kw_args):
print(datetime.datetime.today(), *args, sep=' ', **kw_args)
def usage():
printerr("Usage is: export-to-postgresql.py <database name> [<columns>] [<calls>] [<callchains>] [<pyside-version-1>]");
printerr("where: columns 'all' or 'branches'");
printerr(" calls 'calls' => create calls and call_paths table");
printerr(" callchains 'callchains' => create call_paths table");
printerr(" pyside-version-1 'pyside-version-1' => use pyside version 1");
raise Exception("Too few or bad arguments")
if (len(sys.argv) < 2):
usage()
dbname = sys.argv[1]
if (len(sys.argv) >= 3):
columns = sys.argv[2]
else:
columns = "all"
if columns not in ("all", "branches"):
usage()
branches = (columns == "branches")
for i in range(3,len(sys.argv)):
if (sys.argv[i] == "calls"):
perf_db_export_calls = True
elif (sys.argv[i] == "callchains"):
perf_db_export_callchains = True
elif (sys.argv[i] == "pyside-version-1"):
pass
else:
usage()
output_dir_name = os.getcwd() + "/" + dbname + "-perf-data"
os.mkdir(output_dir_name)
def do_query(q, s):
if (q.exec_(s)):
return
raise Exception("Query failed: " + q.lastError().text())
printdate("Creating database...")
db = QSqlDatabase.addDatabase('QPSQL')
query = QSqlQuery(db)
db.setDatabaseName('postgres')
db.open()
try:
do_query(query, 'CREATE DATABASE ' + dbname)
except:
os.rmdir(output_dir_name)
raise
query.finish()
query.clear()
db.close()
db.setDatabaseName(dbname)
db.open()
query = QSqlQuery(db)
do_query(query, 'SET client_min_messages TO WARNING')
do_query(query, 'CREATE TABLE selected_events ('
'id bigint NOT NULL,'
'name varchar(80))')
do_query(query, 'CREATE TABLE machines ('
'id bigint NOT NULL,'
'pid integer,'
'root_dir varchar(4096))')
do_query(query, 'CREATE TABLE threads ('
'id bigint NOT NULL,'
'machine_id bigint,'
'process_id bigint,'
'pid integer,'
'tid integer)')
do_query(query, 'CREATE TABLE comms ('
'id bigint NOT NULL,'
'comm varchar(16),'
'c_thread_id bigint,'
'c_time bigint,'
'exec_flag boolean)')
do_query(query, 'CREATE TABLE comm_threads ('
'id bigint NOT NULL,'
'comm_id bigint,'
'thread_id bigint)')
do_query(query, 'CREATE TABLE dsos ('
'id bigint NOT NULL,'
'machine_id bigint,'
'short_name varchar(256),'
'long_name varchar(4096),'
'build_id varchar(64))')
do_query(query, 'CREATE TABLE symbols ('
'id bigint NOT NULL,'
'dso_id bigint,'
'sym_start bigint,'
'sym_end bigint,'
'binding integer,'
'name varchar(2048))')
do_query(query, 'CREATE TABLE branch_types ('
'id integer NOT NULL,'
'name varchar(80))')
if branches:
do_query(query, 'CREATE TABLE samples ('
'id bigint NOT NULL,'
'evsel_id bigint,'
'machine_id bigint,'
'thread_id bigint,'
'comm_id bigint,'
'dso_id bigint,'
'symbol_id bigint,'
'sym_offset bigint,'
'ip bigint,'
'time bigint,'
'cpu integer,'
'to_dso_id bigint,'
'to_symbol_id bigint,'
'to_sym_offset bigint,'
'to_ip bigint,'
'branch_type integer,'
'in_tx boolean,'
'call_path_id bigint,'
'insn_count bigint,'
'cyc_count bigint)')
else:
do_query(query, 'CREATE TABLE samples ('
'id bigint NOT NULL,'
'evsel_id bigint,'
'machine_id bigint,'
'thread_id bigint,'
'comm_id bigint,'
'dso_id bigint,'
'symbol_id bigint,'
'sym_offset bigint,'
'ip bigint,'
'time bigint,'
'cpu integer,'
'to_dso_id bigint,'
'to_symbol_id bigint,'
'to_sym_offset bigint,'
'to_ip bigint,'
'period bigint,'
'weight bigint,'
'transaction bigint,'
'data_src bigint,'
'branch_type integer,'
'in_tx boolean,'
'call_path_id bigint,'
'insn_count bigint,'
'cyc_count bigint)')
if perf_db_export_calls or perf_db_export_callchains:
do_query(query, 'CREATE TABLE call_paths ('
'id bigint NOT NULL,'
'parent_id bigint,'
'symbol_id bigint,'
'ip bigint)')
if perf_db_export_calls:
do_query(query, 'CREATE TABLE calls ('
'id bigint NOT NULL,'
'thread_id bigint,'
'comm_id bigint,'
'call_path_id bigint,'
'call_time bigint,'
'return_time bigint,'
'branch_count bigint,'
'call_id bigint,'
'return_id bigint,'
'parent_call_path_id bigint,'
'flags integer,'
'parent_id bigint,'
'insn_count bigint,'
'cyc_count bigint)')
do_query(query, 'CREATE TABLE ptwrite ('
'id bigint NOT NULL,'
'payload bigint,'
'exact_ip boolean)')
do_query(query, 'CREATE TABLE cbr ('
'id bigint NOT NULL,'
'cbr integer,'
'mhz integer,'
'percent integer)')
do_query(query, 'CREATE TABLE mwait ('
'id bigint NOT NULL,'
'hints integer,'
'extensions integer)')
do_query(query, 'CREATE TABLE pwre ('
'id bigint NOT NULL,'
'cstate integer,'
'subcstate integer,'
'hw boolean)')
do_query(query, 'CREATE TABLE exstop ('
'id bigint NOT NULL,'
'exact_ip boolean)')
do_query(query, 'CREATE TABLE pwrx ('
'id bigint NOT NULL,'
'deepest_cstate integer,'
'last_cstate integer,'
'wake_reason integer)')
do_query(query, 'CREATE TABLE context_switches ('
'id bigint NOT NULL,'
'machine_id bigint,'
'time bigint,'
'cpu integer,'
'thread_out_id bigint,'
'comm_out_id bigint,'
'thread_in_id bigint,'
'comm_in_id bigint,'
'flags integer)')
do_query(query, 'CREATE VIEW machines_view AS '
'SELECT '
'id,'
'pid,'
'root_dir,'
'CASE WHEN id=0 THEN \'unknown\' WHEN pid=-1 THEN \'host\' ELSE \'guest\' END AS host_or_guest'
' FROM machines')
do_query(query, 'CREATE VIEW dsos_view AS '
'SELECT '
'id,'
'machine_id,'
'(SELECT host_or_guest FROM machines_view WHERE id = machine_id) AS host_or_guest,'
'short_name,'
'long_name,'
'build_id'
' FROM dsos')
do_query(query, 'CREATE VIEW symbols_view AS '
'SELECT '
'id,'
'name,'
'(SELECT short_name FROM dsos WHERE id=dso_id) AS dso,'
'dso_id,'
'sym_start,'
'sym_end,'
'CASE WHEN binding=0 THEN \'local\' WHEN binding=1 THEN \'global\' ELSE \'weak\' END AS binding'
' FROM symbols')
do_query(query, 'CREATE VIEW threads_view AS '
'SELECT '
'id,'
'machine_id,'
'(SELECT host_or_guest FROM machines_view WHERE id = machine_id) AS host_or_guest,'
'process_id,'
'pid,'
'tid'
' FROM threads')
do_query(query, 'CREATE VIEW comm_threads_view AS '
'SELECT '
'comm_id,'
'(SELECT comm FROM comms WHERE id = comm_id) AS command,'
'thread_id,'
'(SELECT pid FROM threads WHERE id = thread_id) AS pid,'
'(SELECT tid FROM threads WHERE id = thread_id) AS tid'
' FROM comm_threads')
if perf_db_export_calls or perf_db_export_callchains:
do_query(query, 'CREATE VIEW call_paths_view AS '
'SELECT '
'c.id,'
'to_hex(c.ip) AS ip,'
'c.symbol_id,'
'(SELECT name FROM symbols WHERE id = c.symbol_id) AS symbol,'
'(SELECT dso_id FROM symbols WHERE id = c.symbol_id) AS dso_id,'
'(SELECT dso FROM symbols_view WHERE id = c.symbol_id) AS dso_short_name,'
'c.parent_id,'
'to_hex(p.ip) AS parent_ip,'
'p.symbol_id AS parent_symbol_id,'
'(SELECT name FROM symbols WHERE id = p.symbol_id) AS parent_symbol,'
'(SELECT dso_id FROM symbols WHERE id = p.symbol_id) AS parent_dso_id,'
'(SELECT dso FROM symbols_view WHERE id = p.symbol_id) AS parent_dso_short_name'
' FROM call_paths c INNER JOIN call_paths p ON p.id = c.parent_id')
if perf_db_export_calls:
do_query(query, 'CREATE VIEW calls_view AS '
'SELECT '
'calls.id,'
'thread_id,'
'(SELECT pid FROM threads WHERE id = thread_id) AS pid,'
'(SELECT tid FROM threads WHERE id = thread_id) AS tid,'
'(SELECT comm FROM comms WHERE id = comm_id) AS command,'
'call_path_id,'
'to_hex(ip) AS ip,'
'symbol_id,'
'(SELECT name FROM symbols WHERE id = symbol_id) AS symbol,'
'call_time,'
'return_time,'
'return_time - call_time AS elapsed_time,'
'branch_count,'
'insn_count,'
'cyc_count,'
'CASE WHEN cyc_count=0 THEN CAST(0 AS NUMERIC(20, 2)) ELSE CAST((CAST(insn_count AS FLOAT) / cyc_count) AS NUMERIC(20, 2)) END AS IPC,'
'call_id,'
'return_id,'
'CASE WHEN flags=0 THEN \'\' WHEN flags=1 THEN \'no call\' WHEN flags=2 THEN \'no return\' WHEN flags=3 THEN \'no call/return\' WHEN flags=6 THEN \'jump\' ELSE CAST ( flags AS VARCHAR(6) ) END AS flags,'
'parent_call_path_id,'
'calls.parent_id'
' FROM calls INNER JOIN call_paths ON call_paths.id = call_path_id')
do_query(query, 'CREATE VIEW samples_view AS '
'SELECT '
'id,'
'time,'
'cpu,'
'(SELECT pid FROM threads WHERE id = thread_id) AS pid,'
'(SELECT tid FROM threads WHERE id = thread_id) AS tid,'
'(SELECT comm FROM comms WHERE id = comm_id) AS command,'
'(SELECT name FROM selected_events WHERE id = evsel_id) AS event,'
'to_hex(ip) AS ip_hex,'
'(SELECT name FROM symbols WHERE id = symbol_id) AS symbol,'
'sym_offset,'
'(SELECT short_name FROM dsos WHERE id = dso_id) AS dso_short_name,'
'to_hex(to_ip) AS to_ip_hex,'
'(SELECT name FROM symbols WHERE id = to_symbol_id) AS to_symbol,'
'to_sym_offset,'
'(SELECT short_name FROM dsos WHERE id = to_dso_id) AS to_dso_short_name,'
'(SELECT name FROM branch_types WHERE id = branch_type) AS branch_type_name,'
'in_tx,'
'insn_count,'
'cyc_count,'
'CASE WHEN cyc_count=0 THEN CAST(0 AS NUMERIC(20, 2)) ELSE CAST((CAST(insn_count AS FLOAT) / cyc_count) AS NUMERIC(20, 2)) END AS IPC'
' FROM samples')
do_query(query, 'CREATE VIEW ptwrite_view AS '
'SELECT '
'ptwrite.id,'
'time,'
'cpu,'
'to_hex(payload) AS payload_hex,'
'CASE WHEN exact_ip=FALSE THEN \'False\' ELSE \'True\' END AS exact_ip'
' FROM ptwrite'
' INNER JOIN samples ON samples.id = ptwrite.id')
do_query(query, 'CREATE VIEW cbr_view AS '
'SELECT '
'cbr.id,'
'time,'
'cpu,'
'cbr,'
'mhz,'
'percent'
' FROM cbr'
' INNER JOIN samples ON samples.id = cbr.id')
do_query(query, 'CREATE VIEW mwait_view AS '
'SELECT '
'mwait.id,'
'time,'
'cpu,'
'to_hex(hints) AS hints_hex,'
'to_hex(extensions) AS extensions_hex'
' FROM mwait'
' INNER JOIN samples ON samples.id = mwait.id')
do_query(query, 'CREATE VIEW pwre_view AS '
'SELECT '
'pwre.id,'
'time,'
'cpu,'
'cstate,'
'subcstate,'
'CASE WHEN hw=FALSE THEN \'False\' ELSE \'True\' END AS hw'
' FROM pwre'
' INNER JOIN samples ON samples.id = pwre.id')
do_query(query, 'CREATE VIEW exstop_view AS '
'SELECT '
'exstop.id,'
'time,'
'cpu,'
'CASE WHEN exact_ip=FALSE THEN \'False\' ELSE \'True\' END AS exact_ip'
' FROM exstop'
' INNER JOIN samples ON samples.id = exstop.id')
do_query(query, 'CREATE VIEW pwrx_view AS '
'SELECT '
'pwrx.id,'
'time,'
'cpu,'
'deepest_cstate,'
'last_cstate,'
'CASE WHEN wake_reason=1 THEN \'Interrupt\''
' WHEN wake_reason=2 THEN \'Timer Deadline\''
' WHEN wake_reason=4 THEN \'Monitored Address\''
' WHEN wake_reason=8 THEN \'HW\''
' ELSE CAST ( wake_reason AS VARCHAR(2) )'
'END AS wake_reason'
' FROM pwrx'
' INNER JOIN samples ON samples.id = pwrx.id')
do_query(query, 'CREATE VIEW power_events_view AS '
'SELECT '
'samples.id,'
'samples.time,'
'samples.cpu,'
'selected_events.name AS event,'
'FORMAT(\'%6s\', cbr.cbr) AS cbr,'
'FORMAT(\'%6s\', cbr.mhz) AS MHz,'
'FORMAT(\'%5s\', cbr.percent) AS percent,'
'to_hex(mwait.hints) AS hints_hex,'
'to_hex(mwait.extensions) AS extensions_hex,'
'FORMAT(\'%3s\', pwre.cstate) AS cstate,'
'FORMAT(\'%3s\', pwre.subcstate) AS subcstate,'
'CASE WHEN pwre.hw=FALSE THEN \'False\' WHEN pwre.hw=TRUE THEN \'True\' ELSE NULL END AS hw,'
'CASE WHEN exstop.exact_ip=FALSE THEN \'False\' WHEN exstop.exact_ip=TRUE THEN \'True\' ELSE NULL END AS exact_ip,'
'FORMAT(\'%3s\', pwrx.deepest_cstate) AS deepest_cstate,'
'FORMAT(\'%3s\', pwrx.last_cstate) AS last_cstate,'
'CASE WHEN pwrx.wake_reason=1 THEN \'Interrupt\''
' WHEN pwrx.wake_reason=2 THEN \'Timer Deadline\''
' WHEN pwrx.wake_reason=4 THEN \'Monitored Address\''
' WHEN pwrx.wake_reason=8 THEN \'HW\''
' ELSE FORMAT(\'%2s\', pwrx.wake_reason)'
'END AS wake_reason'
' FROM cbr'
' FULL JOIN mwait ON mwait.id = cbr.id'
' FULL JOIN pwre ON pwre.id = cbr.id'
' FULL JOIN exstop ON exstop.id = cbr.id'
' FULL JOIN pwrx ON pwrx.id = cbr.id'
' INNER JOIN samples ON samples.id = coalesce(cbr.id, mwait.id, pwre.id, exstop.id, pwrx.id)'
' INNER JOIN selected_events ON selected_events.id = samples.evsel_id'
' ORDER BY samples.id')
do_query(query, 'CREATE VIEW context_switches_view AS '
'SELECT '
'context_switches.id,'
'context_switches.machine_id,'
'context_switches.time,'
'context_switches.cpu,'
'th_out.pid AS pid_out,'
'th_out.tid AS tid_out,'
'comm_out.comm AS comm_out,'
'th_in.pid AS pid_in,'
'th_in.tid AS tid_in,'
'comm_in.comm AS comm_in,'
'CASE WHEN context_switches.flags = 0 THEN \'in\''
' WHEN context_switches.flags = 1 THEN \'out\''
' WHEN context_switches.flags = 3 THEN \'out preempt\''
' ELSE CAST ( context_switches.flags AS VARCHAR(11) )'
'END AS flags'
' FROM context_switches'
' INNER JOIN threads AS th_out ON th_out.id = context_switches.thread_out_id'
' INNER JOIN threads AS th_in ON th_in.id = context_switches.thread_in_id'
' INNER JOIN comms AS comm_out ON comm_out.id = context_switches.comm_out_id'
' INNER JOIN comms AS comm_in ON comm_in.id = context_switches.comm_in_id')
file_header = struct.pack("!11sii", b"PGCOPY\n\377\r\n\0", 0, 0)
file_trailer = b"\377\377"
def open_output_file(file_name):
path_name = output_dir_name + "/" + file_name
file = open(path_name, "wb+")
file.write(file_header)
return file
def close_output_file(file):
file.write(file_trailer)
file.close()
def copy_output_file_direct(file, table_name):
close_output_file(file)
sql = "COPY " + table_name + " FROM '" + file.name + "' (FORMAT 'binary')"
do_query(query, sql)
# Use COPY FROM STDIN because security may prevent postgres from accessing the files directly
def copy_output_file(file, table_name):
conn = PQconnectdb(toclientstr("dbname = " + dbname))
if (PQstatus(conn)):
raise Exception("COPY FROM STDIN PQconnectdb failed")
file.write(file_trailer)
file.seek(0)
sql = "COPY " + table_name + " FROM STDIN (FORMAT 'binary')"
res = PQexec(conn, toclientstr(sql))
if (PQresultStatus(res) != 4):
raise Exception("COPY FROM STDIN PQexec failed")
data = file.read(65536)
while (len(data)):
ret = PQputCopyData(conn, data, len(data))
if (ret != 1):
raise Exception("COPY FROM STDIN PQputCopyData failed, error " + str(ret))
data = file.read(65536)
ret = PQputCopyEnd(conn, None)
if (ret != 1):
raise Exception("COPY FROM STDIN PQputCopyEnd failed, error " + str(ret))
PQfinish(conn)
def remove_output_file(file):
name = file.name
file.close()
os.unlink(name)
evsel_file = open_output_file("evsel_table.bin")
machine_file = open_output_file("machine_table.bin")
thread_file = open_output_file("thread_table.bin")
comm_file = open_output_file("comm_table.bin")
comm_thread_file = open_output_file("comm_thread_table.bin")
dso_file = open_output_file("dso_table.bin")
symbol_file = open_output_file("symbol_table.bin")
branch_type_file = open_output_file("branch_type_table.bin")
sample_file = open_output_file("sample_table.bin")
if perf_db_export_calls or perf_db_export_callchains:
call_path_file = open_output_file("call_path_table.bin")
if perf_db_export_calls:
call_file = open_output_file("call_table.bin")
ptwrite_file = open_output_file("ptwrite_table.bin")
cbr_file = open_output_file("cbr_table.bin")
mwait_file = open_output_file("mwait_table.bin")
pwre_file = open_output_file("pwre_table.bin")
exstop_file = open_output_file("exstop_table.bin")
pwrx_file = open_output_file("pwrx_table.bin")
context_switches_file = open_output_file("context_switches_table.bin")
def trace_begin():
printdate("Writing to intermediate files...")
# id == 0 means unknown. It is easier to create records for them than replace the zeroes with NULLs
evsel_table(0, "unknown")
machine_table(0, 0, "unknown")
thread_table(0, 0, 0, -1, -1)
comm_table(0, "unknown", 0, 0, 0)
dso_table(0, 0, "unknown", "unknown", "")
symbol_table(0, 0, 0, 0, 0, "unknown")
sample_table(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)
if perf_db_export_calls or perf_db_export_callchains:
call_path_table(0, 0, 0, 0)
call_return_table(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)
unhandled_count = 0
def is_table_empty(table_name):
do_query(query, 'SELECT * FROM ' + table_name + ' LIMIT 1');
if query.next():
return False
return True
def drop(table_name):
do_query(query, 'DROP VIEW ' + table_name + '_view');
do_query(query, 'DROP TABLE ' + table_name);
def trace_end():
printdate("Copying to database...")
copy_output_file(evsel_file, "selected_events")
copy_output_file(machine_file, "machines")
copy_output_file(thread_file, "threads")
copy_output_file(comm_file, "comms")
copy_output_file(comm_thread_file, "comm_threads")
copy_output_file(dso_file, "dsos")
copy_output_file(symbol_file, "symbols")
copy_output_file(branch_type_file, "branch_types")
copy_output_file(sample_file, "samples")
if perf_db_export_calls or perf_db_export_callchains:
copy_output_file(call_path_file, "call_paths")
if perf_db_export_calls:
copy_output_file(call_file, "calls")
copy_output_file(ptwrite_file, "ptwrite")
copy_output_file(cbr_file, "cbr")
copy_output_file(mwait_file, "mwait")
copy_output_file(pwre_file, "pwre")
copy_output_file(exstop_file, "exstop")
copy_output_file(pwrx_file, "pwrx")
copy_output_file(context_switches_file, "context_switches")
printdate("Removing intermediate files...")
remove_output_file(evsel_file)
remove_output_file(machine_file)
remove_output_file(thread_file)
remove_output_file(comm_file)
remove_output_file(comm_thread_file)
remove_output_file(dso_file)
remove_output_file(symbol_file)
remove_output_file(branch_type_file)
remove_output_file(sample_file)
if perf_db_export_calls or perf_db_export_callchains:
remove_output_file(call_path_file)
if perf_db_export_calls:
remove_output_file(call_file)
remove_output_file(ptwrite_file)
remove_output_file(cbr_file)
remove_output_file(mwait_file)
remove_output_file(pwre_file)
remove_output_file(exstop_file)
remove_output_file(pwrx_file)
remove_output_file(context_switches_file)
os.rmdir(output_dir_name)
printdate("Adding primary keys")
do_query(query, 'ALTER TABLE selected_events ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE machines ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE threads ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE comms ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE comm_threads ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE dsos ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE symbols ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE branch_types ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE samples ADD PRIMARY KEY (id)')
if perf_db_export_calls or perf_db_export_callchains:
do_query(query, 'ALTER TABLE call_paths ADD PRIMARY KEY (id)')
if perf_db_export_calls:
do_query(query, 'ALTER TABLE calls ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE ptwrite ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE cbr ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE mwait ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE pwre ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE exstop ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE pwrx ADD PRIMARY KEY (id)')
do_query(query, 'ALTER TABLE context_switches ADD PRIMARY KEY (id)')
printdate("Adding foreign keys")
do_query(query, 'ALTER TABLE threads '
'ADD CONSTRAINT machinefk FOREIGN KEY (machine_id) REFERENCES machines (id),'
'ADD CONSTRAINT processfk FOREIGN KEY (process_id) REFERENCES threads (id)')
do_query(query, 'ALTER TABLE comms '
'ADD CONSTRAINT threadfk FOREIGN KEY (c_thread_id) REFERENCES threads (id)')
do_query(query, 'ALTER TABLE comm_threads '
'ADD CONSTRAINT commfk FOREIGN KEY (comm_id) REFERENCES comms (id),'
'ADD CONSTRAINT threadfk FOREIGN KEY (thread_id) REFERENCES threads (id)')
do_query(query, 'ALTER TABLE dsos '
'ADD CONSTRAINT machinefk FOREIGN KEY (machine_id) REFERENCES machines (id)')
do_query(query, 'ALTER TABLE symbols '
'ADD CONSTRAINT dsofk FOREIGN KEY (dso_id) REFERENCES dsos (id)')
do_query(query, 'ALTER TABLE samples '
'ADD CONSTRAINT evselfk FOREIGN KEY (evsel_id) REFERENCES selected_events (id),'
'ADD CONSTRAINT machinefk FOREIGN KEY (machine_id) REFERENCES machines (id),'
'ADD CONSTRAINT threadfk FOREIGN KEY (thread_id) REFERENCES threads (id),'
'ADD CONSTRAINT commfk FOREIGN KEY (comm_id) REFERENCES comms (id),'
'ADD CONSTRAINT dsofk FOREIGN KEY (dso_id) REFERENCES dsos (id),'
'ADD CONSTRAINT symbolfk FOREIGN KEY (symbol_id) REFERENCES symbols (id),'
'ADD CONSTRAINT todsofk FOREIGN KEY (to_dso_id) REFERENCES dsos (id),'
'ADD CONSTRAINT tosymbolfk FOREIGN KEY (to_symbol_id) REFERENCES symbols (id)')
if perf_db_export_calls or perf_db_export_callchains:
do_query(query, 'ALTER TABLE call_paths '
'ADD CONSTRAINT parentfk FOREIGN KEY (parent_id) REFERENCES call_paths (id),'
'ADD CONSTRAINT symbolfk FOREIGN KEY (symbol_id) REFERENCES symbols (id)')
if perf_db_export_calls:
do_query(query, 'ALTER TABLE calls '
'ADD CONSTRAINT threadfk FOREIGN KEY (thread_id) REFERENCES threads (id),'
'ADD CONSTRAINT commfk FOREIGN KEY (comm_id) REFERENCES comms (id),'
'ADD CONSTRAINT call_pathfk FOREIGN KEY (call_path_id) REFERENCES call_paths (id),'
'ADD CONSTRAINT callfk FOREIGN KEY (call_id) REFERENCES samples (id),'
'ADD CONSTRAINT returnfk FOREIGN KEY (return_id) REFERENCES samples (id),'
'ADD CONSTRAINT parent_call_pathfk FOREIGN KEY (parent_call_path_id) REFERENCES call_paths (id)')
do_query(query, 'CREATE INDEX pcpid_idx ON calls (parent_call_path_id)')
do_query(query, 'CREATE INDEX pid_idx ON calls (parent_id)')
do_query(query, 'ALTER TABLE comms ADD has_calls boolean')
do_query(query, 'UPDATE comms SET has_calls = TRUE WHERE comms.id IN (SELECT DISTINCT comm_id FROM calls)')
do_query(query, 'ALTER TABLE ptwrite '
'ADD CONSTRAINT idfk FOREIGN KEY (id) REFERENCES samples (id)')
do_query(query, 'ALTER TABLE cbr '
'ADD CONSTRAINT idfk FOREIGN KEY (id) REFERENCES samples (id)')
do_query(query, 'ALTER TABLE mwait '
'ADD CONSTRAINT idfk FOREIGN KEY (id) REFERENCES samples (id)')
do_query(query, 'ALTER TABLE pwre '
'ADD CONSTRAINT idfk FOREIGN KEY (id) REFERENCES samples (id)')
do_query(query, 'ALTER TABLE exstop '
'ADD CONSTRAINT idfk FOREIGN KEY (id) REFERENCES samples (id)')
do_query(query, 'ALTER TABLE pwrx '
'ADD CONSTRAINT idfk FOREIGN KEY (id) REFERENCES samples (id)')
do_query(query, 'ALTER TABLE context_switches '
'ADD CONSTRAINT machinefk FOREIGN KEY (machine_id) REFERENCES machines (id),'
'ADD CONSTRAINT toutfk FOREIGN KEY (thread_out_id) REFERENCES threads (id),'
'ADD CONSTRAINT tinfk FOREIGN KEY (thread_in_id) REFERENCES threads (id),'
'ADD CONSTRAINT coutfk FOREIGN KEY (comm_out_id) REFERENCES comms (id),'
'ADD CONSTRAINT cinfk FOREIGN KEY (comm_in_id) REFERENCES comms (id)')
printdate("Dropping unused tables")
if is_table_empty("ptwrite"):
drop("ptwrite")
if is_table_empty("mwait") and is_table_empty("pwre") and is_table_empty("exstop") and is_table_empty("pwrx"):
do_query(query, 'DROP VIEW power_events_view');
drop("mwait")
drop("pwre")
drop("exstop")
drop("pwrx")
if is_table_empty("cbr"):
drop("cbr")
if is_table_empty("context_switches"):
drop("context_switches")
if (unhandled_count):
printdate("Warning: ", unhandled_count, " unhandled events")
printdate("Done")
def trace_unhandled(event_name, context, event_fields_dict):
global unhandled_count
unhandled_count += 1
def sched__sched_switch(*x):
pass
def evsel_table(evsel_id, evsel_name, *x):
evsel_name = toserverstr(evsel_name)
n = len(evsel_name)
fmt = "!hiqi" + str(n) + "s"
value = struct.pack(fmt, 2, 8, evsel_id, n, evsel_name)
evsel_file.write(value)
def machine_table(machine_id, pid, root_dir, *x):
root_dir = toserverstr(root_dir)
n = len(root_dir)
fmt = "!hiqiii" + str(n) + "s"
value = struct.pack(fmt, 3, 8, machine_id, 4, pid, n, root_dir)
machine_file.write(value)
def thread_table(thread_id, machine_id, process_id, pid, tid, *x):
value = struct.pack("!hiqiqiqiiii", 5, 8, thread_id, 8, machine_id, 8, process_id, 4, pid, 4, tid)
thread_file.write(value)
def comm_table(comm_id, comm_str, thread_id, time, exec_flag, *x):
comm_str = toserverstr(comm_str)
n = len(comm_str)
fmt = "!hiqi" + str(n) + "s" + "iqiqiB"
value = struct.pack(fmt, 5, 8, comm_id, n, comm_str, 8, thread_id, 8, time, 1, exec_flag)
comm_file.write(value)
def comm_thread_table(comm_thread_id, comm_id, thread_id, *x):
fmt = "!hiqiqiq"
value = struct.pack(fmt, 3, 8, comm_thread_id, 8, comm_id, 8, thread_id)
comm_thread_file.write(value)
def dso_table(dso_id, machine_id, short_name, long_name, build_id, *x):
short_name = toserverstr(short_name)
long_name = toserverstr(long_name)
build_id = toserverstr(build_id)
n1 = len(short_name)
n2 = len(long_name)
n3 = len(build_id)
fmt = "!hiqiqi" + str(n1) + "si" + str(n2) + "si" + str(n3) + "s"
value = struct.pack(fmt, 5, 8, dso_id, 8, machine_id, n1, short_name, n2, long_name, n3, build_id)
dso_file.write(value)
def symbol_table(symbol_id, dso_id, sym_start, sym_end, binding, symbol_name, *x):
symbol_name = toserverstr(symbol_name)
n = len(symbol_name)
fmt = "!hiqiqiqiqiii" + str(n) + "s"
value = struct.pack(fmt, 6, 8, symbol_id, 8, dso_id, 8, sym_start, 8, sym_end, 4, binding, n, symbol_name)
symbol_file.write(value)
def branch_type_table(branch_type, name, *x):
name = toserverstr(name)
n = len(name)
fmt = "!hiii" + str(n) + "s"
value = struct.pack(fmt, 2, 4, branch_type, n, name)
branch_type_file.write(value)
def sample_table(sample_id, evsel_id, machine_id, thread_id, comm_id, dso_id, symbol_id, sym_offset, ip, time, cpu, to_dso_id, to_symbol_id, to_sym_offset, to_ip, period, weight, transaction, data_src, branch_type, in_tx, call_path_id, insn_cnt, cyc_cnt, *x):
if branches:
value = struct.pack("!hiqiqiqiqiqiqiqiqiqiqiiiqiqiqiqiiiBiqiqiq", 20, 8, sample_id, 8, evsel_id, 8, machine_id, 8, thread_id, 8, comm_id, 8, dso_id, 8, symbol_id, 8, sym_offset, 8, ip, 8, time, 4, cpu, 8, to_dso_id, 8, to_symbol_id, 8, to_sym_offset, 8, to_ip, 4, branch_type, 1, in_tx, 8, call_path_id, 8, insn_cnt, 8, cyc_cnt)
else:
value = struct.pack("!hiqiqiqiqiqiqiqiqiqiqiiiqiqiqiqiqiqiqiqiiiBiqiqiq", 24, 8, sample_id, 8, evsel_id, 8, machine_id, 8, thread_id, 8, comm_id, 8, dso_id, 8, symbol_id, 8, sym_offset, 8, ip, 8, time, 4, cpu, 8, to_dso_id, 8, to_symbol_id, 8, to_sym_offset, 8, to_ip, 8, period, 8, weight, 8, transaction, 8, data_src, 4, branch_type, 1, in_tx, 8, call_path_id, 8, insn_cnt, 8, cyc_cnt)
sample_file.write(value)
def call_path_table(cp_id, parent_id, symbol_id, ip, *x):
fmt = "!hiqiqiqiq"
value = struct.pack(fmt, 4, 8, cp_id, 8, parent_id, 8, symbol_id, 8, ip)
call_path_file.write(value)
def call_return_table(cr_id, thread_id, comm_id, call_path_id, call_time, return_time, branch_count, call_id, return_id, parent_call_path_id, flags, parent_id, insn_cnt, cyc_cnt, *x):
fmt = "!hiqiqiqiqiqiqiqiqiqiqiiiqiqiq"
value = struct.pack(fmt, 14, 8, cr_id, 8, thread_id, 8, comm_id, 8, call_path_id, 8, call_time, 8, return_time, 8, branch_count, 8, call_id, 8, return_id, 8, parent_call_path_id, 4, flags, 8, parent_id, 8, insn_cnt, 8, cyc_cnt)
call_file.write(value)
def ptwrite(id, raw_buf):
data = struct.unpack_from("<IQ", raw_buf)
flags = data[0]
payload = data[1]
exact_ip = flags & 1
value = struct.pack("!hiqiqiB", 3, 8, id, 8, payload, 1, exact_ip)
ptwrite_file.write(value)
def cbr(id, raw_buf):
data = struct.unpack_from("<BBBBII", raw_buf)
cbr = data[0]
MHz = (data[4] + 500) / 1000
percent = ((cbr * 1000 / data[2]) + 5) / 10
value = struct.pack("!hiqiiiiii", 4, 8, id, 4, cbr, 4, int(MHz), 4, int(percent))
cbr_file.write(value)
def mwait(id, raw_buf):
data = struct.unpack_from("<IQ", raw_buf)
payload = data[1]
hints = payload & 0xff
extensions = (payload >> 32) & 0x3
value = struct.pack("!hiqiiii", 3, 8, id, 4, hints, 4, extensions)
mwait_file.write(value)
def pwre(id, raw_buf):
data = struct.unpack_from("<IQ", raw_buf)
payload = data[1]
hw = (payload >> 7) & 1
cstate = (payload >> 12) & 0xf
subcstate = (payload >> 8) & 0xf
value = struct.pack("!hiqiiiiiB", 4, 8, id, 4, cstate, 4, subcstate, 1, hw)
pwre_file.write(value)
def exstop(id, raw_buf):
data = struct.unpack_from("<I", raw_buf)
flags = data[0]
exact_ip = flags & 1
value = struct.pack("!hiqiB", 2, 8, id, 1, exact_ip)
exstop_file.write(value)
def pwrx(id, raw_buf):
data = struct.unpack_from("<IQ", raw_buf)
payload = data[1]
deepest_cstate = payload & 0xf
last_cstate = (payload >> 4) & 0xf
wake_reason = (payload >> 8) & 0xf
value = struct.pack("!hiqiiiiii", 4, 8, id, 4, deepest_cstate, 4, last_cstate, 4, wake_reason)
pwrx_file.write(value)
def synth_data(id, config, raw_buf, *x):
if config == 0:
ptwrite(id, raw_buf)
elif config == 1:
mwait(id, raw_buf)
elif config == 2:
pwre(id, raw_buf)
elif config == 3:
exstop(id, raw_buf)
elif config == 4:
pwrx(id, raw_buf)
elif config == 5:
cbr(id, raw_buf)
def context_switch_table(id, machine_id, time, cpu, thread_out_id, comm_out_id, thread_in_id, comm_in_id, flags, *x):
fmt = "!hiqiqiqiiiqiqiqiqii"
value = struct.pack(fmt, 9, 8, id, 8, machine_id, 8, time, 4, cpu, 8, thread_out_id, 8, comm_out_id, 8, thread_in_id, 8, comm_in_id, 4, flags)
context_switches_file.write(value)