Re: [PATCH] perf script: add script to profile and resolve physical mem type

From: Stephane Eranian
Date: Tue Oct 17 2017 - 15:58:31 EST


On Tue, Oct 17, 2017 at 12:54 PM, Liang, Kan <kan.liang@xxxxxxxxx> wrote:
>> On Mon, Oct 16, 2017 at 3:26 PM, <kan.liang@xxxxxxxxx> wrote:
>> > From: Kan Liang <Kan.liang@xxxxxxxxx>
>> >
>> > There could be different types of memory in the system. E.g normal
>> > System Memory, Persistent Memory. To understand how the workload
>> maps to
>> > those memories, it's important to know the I/O statistics on different
>> > type of memorys. Perf can collect address maps with physical addresses,
>> > but those are raw data. It still needs extra work to resolve the
>> > physical addresses.
>> > Providing a script to facilitate the physical addresses resolving and
>> > I/O statistics.
>> >
>> > Profiling with mem-loads and mem-stores if they are available.
>> > Looking up the physical address samples in /proc/iomem
>> > Providing memory type summary
>> >
>> > Here is an example
>> > #perf script record mem-phys-addr -- pmem_test_kernel
>> > [ perf record: Woken up 32 times to write data ]
>> > [ perf record: Captured and wrote 7.797 MB perf.data (101995 samples) ]
>> > #perf script report mem-phys-addr
>> > Memory type summary
>> >
>> > Event: mem-loads
>> > Memory type count percentage
>> > ---------------------------------------- ----------- -----------
>> > Persistent Memory 43740 60.6%
>> > System RAM 27179 37.7%
>> > N/A 1268 1.8%
>> >
>> > Event: mem-stores
>> > Memory type count percentage
>> > ---------------------------------------- ----------- -----------
>> > System RAM 24508 82.2%
>> > N/A 5140 17.2%
>> > Persistent Memory 160 0.5%
>> >
>> > Signed-off-by: Kan Liang <Kan.liang@xxxxxxxxx>
>> > ---
>> > tools/perf/scripts/python/bin/mem-phys-addr-record | 30 ++++++
>> > tools/perf/scripts/python/bin/mem-phys-addr-report | 3 +
>> > tools/perf/scripts/python/mem-phys-addr.py | 109
>> +++++++++++++++++++++
>> > .../util/scripting-engines/trace-event-python.c | 2 +
>> > 4 files changed, 144 insertions(+)
>> > create mode 100644 tools/perf/scripts/python/bin/mem-phys-addr-
>> record
>> > create mode 100644 tools/perf/scripts/python/bin/mem-phys-addr-report
>> > create mode 100644 tools/perf/scripts/python/mem-phys-addr.py
>> >
>> > diff --git a/tools/perf/scripts/python/bin/mem-phys-addr-record
>> b/tools/perf/scripts/python/bin/mem-phys-addr-record
>> > new file mode 100644
>> > index 0000000..395b256
>> > --- /dev/null
>> > +++ b/tools/perf/scripts/python/bin/mem-phys-addr-record
>> > @@ -0,0 +1,30 @@
>> > +#!/bin/bash
>> > +
>> > +#
>> > +# Profiling physical memory accesses
>> > +#
>> > +
>> > +load=`perf list pmu | grep mem-loads`
>> > +store=`perf list pmu | grep mem-stores`
>> > +if [ -z "$load" ] && [ -z "$store" ] ; then
>> > + echo "There is no mem-loads or mem-stores support"
>> > + exit 1
>> > +fi
>> > +
>> > +arg="-e"
>> > +if [ ! -z "$store" ] ; then
>> > + arg="$arg mem-stores:P"
>> > +fi
>> > +
>> > +if [ ! -z "$load" ] ; then
>> > + if [ ! -z "$store" ] ; then
>> > + arg="$arg,mem-loads:P"
>> > + else
>> > + arg="$arg mem-loads:P"
>> > + fi
>> > + arg="$arg -W"
>> > +fi
>> > +
>> > +arg="$arg -d --phys-data"
>> > +
>> > +perf record $arg $@
>> > diff --git a/tools/perf/scripts/python/bin/mem-phys-addr-report
>> b/tools/perf/scripts/python/bin/mem-phys-addr-report
>> > new file mode 100644
>> > index 0000000..3f2b847
>> > --- /dev/null
>> > +++ b/tools/perf/scripts/python/bin/mem-phys-addr-report
>> > @@ -0,0 +1,3 @@
>> > +#!/bin/bash
>> > +# description: resolve physical address samples
>> > +perf script $@ -s "$PERF_EXEC_PATH"/scripts/python/mem-phys-addr.py
>> > diff --git a/tools/perf/scripts/python/mem-phys-addr.py
>> b/tools/perf/scripts/python/mem-phys-addr.py
>> > new file mode 100644
>> > index 0000000..73b3a63
>> > --- /dev/null
>> > +++ b/tools/perf/scripts/python/mem-phys-addr.py
>> > @@ -0,0 +1,109 @@
>> > +# mem-phys-addr.py: Resolve physical address samples
>> > +# Copyright (c) 2017, 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 division
>> > +import os
>> > +import sys
>> > +import struct
>> > +import re
>> > +import bisect
>> > +import collections
>> > +
>> > +sys.path.append(os.environ['PERF_EXEC_PATH'] + \
>> > + '/scripts/python/Perf-Trace-Util/lib/Perf/Trace')
>> > +
>> > +system_ram = []
>> > +pmem = []
>> > +f = None
>> > +load_event = ('mem-loads', '0x1cd')
>> > +store_event = ('mem-stores', '0x82d0');
>>
>> I don't like the fact that you are mixing DLA and Load Latency.
>> The two mechanism do not operate the same way and any attempt
>> at comparing the loads and stores lead to misinterpretations.
>>
>
> OK. I will only keep "-d --phys-data" options as default.
> For the event, is only mem-loads good enough as default event?
> Or should we just let the user fill up the event?
>
Why not use 0x81d0 to be symmetrical with the stores?


> Thanks,
> Kan
>
>> > +load_mem_type_cnt = collections.Counter()
>> > +store_mem_type_cnt = collections.Counter()
>> > +
>> > +def parse_iomem():
>> > + global f
>> > + f = open('/proc/iomem', 'r')
>> > + for i, j in enumerate(f):
>> > + m = re.split('-|:',j,2)
>> > + if m[2].strip() == 'System RAM':
>> > + system_ram.append(long(m[0], 16))
>> > + system_ram.append(long(m[1], 16))
>> > + if m[2].strip() == 'Persistent Memory':
>> > + pmem.append(long(m[0], 16))
>> > + pmem.append(long(m[1], 16))
>> > +
>> > +def print_memory_type():
>> > + print "Memory type summary\n"
>> > + print "Event: mem-loads"
>> > + print "%-40s %10s %10s\n" % ("Memory type", "count",
>> "percentage"),
>> > + print "%-40s %10s %10s\n" % ("----------------------------------------", \
>> > + "-----------", "-----------"),
>> > + total = sum(load_mem_type_cnt.values())
>> > + for mem_type, count in sorted(load_mem_type_cnt.most_common(),
>> \
>> > + key = lambda(k, v): (v, k), reverse = True):
>> > + print "%-40s %10d %10.1f%%\n" % (mem_type, count, 100 *
>> count / total),
>> > + print "\n\n"
>> > + print "Event: mem-stores"
>> > + print "%-40s %10s %10s\n" % ("Memory type", "count",
>> "percentage"),
>> > + print "%-40s %10s %10s\n" % ("----------------------------------------", \
>> > + "-----------", "-----------"),
>> > + total = sum(store_mem_type_cnt.values())
>> > + for mem_type, count in sorted(store_mem_type_cnt.most_common(),
>> \
>> > + key = lambda(k, v): (v, k), reverse = True):
>> > + print "%-40s %10d %10.1f%%\n" % (mem_type, count, 100 *
>> count / total),
>> > +
>> > +def trace_begin():
>> > + parse_iomem()
>> > +
>> > +def trace_end():
>> > + print_memory_type()
>> > + f.close()
>> > +
>> > +def is_system_ram(phys_addr):
>> > + #/proc/iomem is sorted
>> > + position = bisect.bisect(system_ram, phys_addr)
>> > + if position % 2 == 0:
>> > + return False
>> > + return True
>> > +
>> > +def is_persistent_mem(phys_addr):
>> > + position = bisect.bisect(pmem, phys_addr)
>> > + if position % 2 == 0:
>> > + return False
>> > + return True
>> > +
>> > +def find_memory_type(phys_addr):
>> > + if phys_addr == 0:
>> > + return "N/A"
>> > + if is_system_ram(phys_addr):
>> > + return "System RAM"
>> > +
>> > + if is_persistent_mem(phys_addr):
>> > + return "Persistent Memory"
>> > +
>> > + #slow path, search all
>> > + f.seek(0, 0)
>> > + for j in f:
>> > + m = re.split('-|:',j,2)
>> > + if long(m[0], 16) <= phys_addr <= long(m[1], 16):
>> > + return m[2]
>> > + return "N/A"
>> > +
>> > +def process_event(param_dict):
>> > + name = param_dict["ev_name"]
>> > + sample = param_dict["sample"]
>> > + phys_addr = sample["phys_addr"]
>> > +
>> > + if any(x in name for x in load_event):
>> > + load_mem_type_cnt[find_memory_type(phys_addr)] += 1
>> > + if any(x in name for x in store_event):
>> > + store_mem_type_cnt[find_memory_type(phys_addr)] += 1
>> > diff --git a/tools/perf/util/scripting-engines/trace-event-python.c
>> b/tools/perf/util/scripting-engines/trace-event-python.c
>> > index c7187f0..8cd6317 100644
>> > --- a/tools/perf/util/scripting-engines/trace-event-python.c
>> > +++ b/tools/perf/util/scripting-engines/trace-event-python.c
>> > @@ -500,6 +500,8 @@ static PyObject *get_perf_sample_dict(struct
>> perf_sample *sample,
>> > PyLong_FromUnsignedLongLong(sample->time));
>> > pydict_set_item_string_decref(dict_sample, "period",
>> > PyLong_FromUnsignedLongLong(sample->period));
>> > + pydict_set_item_string_decref(dict_sample, "phys_addr",
>> > + PyLong_FromUnsignedLongLong(sample->phys_addr));
>> > set_sample_read_in_dict(dict_sample, sample, evsel);
>> > pydict_set_item_string_decref(dict, "sample", dict_sample);
>> >
>> > --
>> > 2.7.4
>> >