Commit 7e93ae8b authored by Ben Gamari's avatar Ben Gamari 🐢

rts: Post ticky entry counts to the eventlog

We currently only post the entry counters, not the other global
counters as in my experience the former are more useful. We use the heap
profiler's census period to decide when to dump.

Also spruces up the documentation surrounding ticky-ticky a bit.
parent 69bfbc21
Pipeline #27748 failed with stages
in 375 minutes and 26 seconds
......@@ -755,3 +755,34 @@ intended to provide insight into fragmentation of the non-moving heap.
:field Word32: number of live blocks.
Describes the occupancy of the *blk_sz* sub-heap.
Ticky counters
~~~~~~~~~~~~~~
Programs compiled with :ghc-flag:`-ticky` and :ghc-flag:`-eventlog` and invoked
with ``+RTS -lT`` will emit periodic samples of the ticky entry counters to the
eventlog.
.. event-type:: TICKY_COUNTER_DEF
:tag: 210
:length: variable
:field Word64: counter ID
:field Word16: arity/field count
:field String: argument kinds. This is the same as the synonymous field in the
textual ticky summary.
:field String: counter name
Defines a ticky counter.
.. event-type:: TICKY_COUNTER_SAMPLE
:tag: 211
:length: fixed
:field Word64: counter ID
:field Word64: number of times closures of this type has been entered.
:field Word64: number of allocations (words)
:field Word64: number of times this has been allocated (words). Only
produced for modules compiled with :ghc-flag:`-ticky-allocd`.
Records the counter statistics at a moment in time.
......@@ -118,5 +118,3 @@
-syslib
-this-component-id
-ticky-LNE
-ticky-allocd
-ticky-dyn-thunk
......@@ -1681,11 +1681,27 @@ Using “ticky-ticky” profiling (for implementors)
single: ticky-ticky profiling
.. ghc-flag:: -ticky
:shortdesc: :ref:`Turn on ticky-ticky profiling <ticky-ticky>`
:shortdesc: Turn on :ref:`ticky-ticky profiling <ticky-ticky>`
:type: dynamic
:category:
Enable ticky-ticky profiling.
Enable ticky-ticky profiling. By default this only tracks the allocations
*by* each closure type. See :ghc-flag:`-ticky-allocd` to keep track of
allocations *of* each closure type as well.
.. ghc-flag:: -ticky-allocd
:shortdesc: Track the number of times each closure type is allocated.
:type: dynamic
:category:
Keep track of how much each closure type is allocated.
.. ghc-flag:: -ticky-dyn-thunk
:shortdesc: Track allocations of dynamic thunks
:type: dynamic
:category:
Track allocations of dynamic thunks.
Because ticky-ticky profiling requires a certain familiarity with GHC
internals, we have moved the documentation to the GHC developers wiki.
......
......@@ -154,12 +154,15 @@
#define EVENT_CONC_UPD_REM_SET_FLUSH 206
#define EVENT_NONMOVING_HEAP_CENSUS 207
#define EVENT_TICKY_COUNTER_DEF 210
#define EVENT_TICKY_COUNTER_SAMPLE 211
/*
* The highest event code +1 that ghc itself emits. Note that some event
* ranges higher than this are reserved but not currently emitted by ghc.
* This must match the size of the EventDesc[] array in EventLog.c
*/
#define NUM_GHC_EVENT_TAGS 208
#define NUM_GHC_EVENT_TAGS 212
#if 0 /* DEPRECATED EVENTS: */
/* we don't actually need to record the thread, it's implicit */
......
......@@ -176,6 +176,7 @@ typedef struct _TRACE_FLAGS {
bool nonmoving_gc; /* trace nonmoving GC events */
bool sparks_sampled; /* trace spark events by a sampled method */
bool sparks_full; /* trace spark events 100% accurately */
bool ticky; /* trace ticky-ticky samples */
bool user; /* trace user events (emitted from Haskell code) */
char *trace_output; /* output filename for eventlog */
} TRACE_FLAGS;
......
......@@ -20,6 +20,12 @@ static bool do_prof_ticks = false; // enable profiling ticks
static bool do_heap_prof_ticks = false; // enable heap profiling ticks
// Sampling of Ticky-Ticky profiler to eventlog
#if defined(TICKY_TICKY) && defined(TRACING)
static int ticks_to_ticky_sample = 0;
bool performTickySample = false;
#endif
// Number of ticks until next heap census
static int ticks_to_heap_profile;
......@@ -83,6 +89,16 @@ handleProfTick(void)
}
#endif
#if defined(TICKY_TICKY) && defined(TRACING)
if (RtsFlags.TraceFlags.ticky) {
ticks_to_ticky_sample--;
if (ticks_to_ticky_sample <= 0) {
ticks_to_ticky_sample = RtsFlags.ProfFlags.heapProfileIntervalTicks;
performTickySample = true;
}
}
#endif
if (RELAXED_LOAD(&do_heap_prof_ticks)) {
ticks_to_heap_profile--;
if (ticks_to_heap_profile <= 0) {
......
......@@ -17,5 +17,6 @@ void stopHeapProfTimer ( void );
void startHeapProfTimer ( void );
extern bool performHeapProfile;
extern bool performTickySample;
#include "EndPrivate.h"
......@@ -235,6 +235,7 @@ void initRtsFlagsDefaults(void)
RtsFlags.TraceFlags.sparks_sampled= false;
RtsFlags.TraceFlags.sparks_full = false;
RtsFlags.TraceFlags.user = false;
RtsFlags.TraceFlags.ticky = false;
RtsFlags.TraceFlags.trace_output = NULL;
#endif
......@@ -403,6 +404,9 @@ usage_text[] = {
" p par spark events (sampled)",
" f par spark events (full detail)",
" u user events (emitted from Haskell code)",
#if defined(TICKY_TICKY)
" T ticky-ticky counter samples",
#endif
" a all event classes above",
# if defined(DEBUG)
" t add time stamps (only useful with -v)",
......@@ -1855,6 +1859,11 @@ static void normaliseRtsOpts (void)
"the compacting collector.");
errorUsage();
}
if (RtsFlags.TraceFlags.ticky && RtsFlags.TickyFlags.showTickyStats) {
barf("The ticky-ticky eventlog output cannot be used in conjunction with\n"
"+RTS -r<file>.");
}
}
static void errorUsage (void)
......@@ -2297,6 +2306,15 @@ static void read_trace_flags(const char *arg)
RtsFlags.TraceFlags.user = enabled;
enabled = true;
break;
case 'T':
#if defined(TICKY_TICKY)
RtsFlags.TraceFlags.ticky = enabled;
enabled = true;
break;
#else
errorBelch("Program not compiled with ticky-ticky support");
break;
#endif
default:
errorBelch("unknown trace option: %c",*c);
break;
......
......@@ -487,6 +487,17 @@ hs_exit_(bool wait_foreign)
*/
exitTimer(true);
/*
* Dump the ticky counter definitions
* We do this at the end of execution since tickers are registered in the
* course of program execution.
*/
#if defined(TICKY_TICKY) && defined(TRACING)
if (RtsFlags.TraceFlags.ticky) {
emitTickyCounterDefs();
}
#endif
// set the terminal settings back to what they were
#if !defined(mingw32_HOST_OS)
resetTerminalSettings();
......
......@@ -10,6 +10,8 @@
#include "PosixSource.h"
#include "Rts.h"
#include "eventlog/EventLog.h"
/* Catch-all top-level counter struct. Allocations from CAFs will go
* here.
*/
......@@ -46,6 +48,10 @@ static void printRegisteredCounterInfo (FILE *); /* fwd decl */
void
PrintTickyInfo(void)
{
if (RtsFlags.TraceFlags.ticky) {
barf("Ticky eventlog output can't be used with +RTS -r<file>");
}
unsigned long i;
unsigned long tot_thk_enters = ENT_STATIC_THK_MANY_ctr + ENT_DYN_THK_MANY_ctr
......@@ -374,4 +380,19 @@ printRegisteredCounterInfo (FILE *tf)
}
}
void emitTickyCounterDefs()
{
#if defined(TRACING)
postTickyCounterDefs(ticky_entry_ctrs);
#endif
}
void emitTickyCounterSamples()
{
#if defined(TRACING)
postTickyCounterSamples(ticky_entry_ctrs);
#endif
}
#endif /* TICKY_TICKY */
......@@ -8,4 +8,11 @@
#pragma once
RTS_PRIVATE void PrintTickyInfo(void);
#include "BeginPrivate.h"
void PrintTickyInfo(void);
void emitTickyCounterSamples(void);
void emitTickyCounterDefs(void);
#include "EndPrivate.h"
......@@ -119,7 +119,9 @@ char *EventDesc[] = {
[EVENT_CONC_SWEEP_BEGIN] = "Begin concurrent sweep",
[EVENT_CONC_SWEEP_END] = "End concurrent sweep",
[EVENT_CONC_UPD_REM_SET_FLUSH] = "Update remembered set flushed",
[EVENT_NONMOVING_HEAP_CENSUS] = "Nonmoving heap census"
[EVENT_NONMOVING_HEAP_CENSUS] = "Nonmoving heap census",
[EVENT_TICKY_COUNTER_DEF] = "Ticky-ticky entry counter definition",
[EVENT_TICKY_COUNTER_SAMPLE] = "Ticky-ticky entry counter sample",
};
// Event type.
......@@ -487,6 +489,14 @@ init_event_types(void)
eventTypes[t].size = 13;
break;
case EVENT_TICKY_COUNTER_DEF: // (counter_id, arity, arg_kinds, name)
eventTypes[t].size = EVENT_SIZE_DYNAMIC;
break;
case EVENT_TICKY_COUNTER_SAMPLE: // (counter_id, entry_count, allocs, allocd)
eventTypes[t].size = 8*4;
break;
default:
continue; /* ignore deprecated events */
}
......@@ -1472,6 +1482,53 @@ void postProfBegin(void)
}
#endif /* PROFILING */
#if defined(TICKY_TICKY)
static void postTickyCounterDef(EventsBuf *eb, StgEntCounter *p)
{
StgWord len = 8 + 2 + strlen(p->arg_kinds)+1 + strlen(p->str)+1;
ensureRoomForVariableEvent(eb, len);
postEventHeader(eb, EVENT_TICKY_COUNTER_DEF);
postPayloadSize(eb, len);
postWord64(eb, (uint64_t) p);
postWord16(eb, (uint16_t) p->arity);
postString(eb, p->arg_kinds);
postString(eb, p->str);
}
void postTickyCounterDefs(StgEntCounter *counters)
{
ACQUIRE_LOCK(&eventBufMutex);
for (StgEntCounter *p = counters; p != NULL; p = p->link) {
postTickyCounterDef(&eventBuf, p);
}
RELEASE_LOCK(&eventBufMutex);
}
static void postTickyCounterSample(EventsBuf *eb, StgEntCounter *p)
{
if ( p->entry_count == 0
&& p->allocs == 0
&& p->allocd == 0)
return;
ensureRoomForEvent(eb, EVENT_TICKY_COUNTER_SAMPLE);
postEventHeader(eb, EVENT_TICKY_COUNTER_SAMPLE);
postWord64(eb, (uint64_t) p);
postWord64(eb, p->entry_count);
postWord64(eb, p->allocs);
postWord64(eb, p->allocd);
}
void postTickyCounterSamples(StgEntCounter *counters)
{
ACQUIRE_LOCK(&eventBufMutex);
for (StgEntCounter *p = counters; p != NULL; p = p->link) {
postTickyCounterSample(&eventBuf, p);
}
RELEASE_LOCK(&eventBufMutex);
}
#endif /* TICKY_TICKY */
void printAndClearEventBuf (EventsBuf *ebuf)
{
closeBlockMarker(ebuf);
......
......@@ -173,6 +173,11 @@ void postConcMarkEnd(StgWord32 marked_obj_count);
void postNonmovingHeapCensus(int log_blk_size,
const struct NonmovingAllocCensus *census);
#if defined(TICKY_TICKY)
void postTickyCounterDefs(StgEntCounter *p);
void postTickyCounterSamples(StgEntCounter *p);
#endif /* TICKY_TICKY */
#else /* !TRACING */
INLINE_HEADER void postSchedEvent (Capability *cap STG_UNUSED,
......
......@@ -38,6 +38,7 @@
#include "Sanity.h"
#include "BlockAlloc.h"
#include "ProfHeap.h"
#include "Proftimer.h"
#include "Weak.h"
#include "Prelude.h"
#include "RtsSignals.h"
......@@ -52,6 +53,7 @@
#include "CNF.h"
#include "RtsFlags.h"
#include "NonMoving.h"
#include "Ticky.h"
#include <string.h> // for memset()
#include <unistd.h>
......@@ -903,6 +905,16 @@ GarbageCollect (uint32_t collect_gen,
ACQUIRE_SM_LOCK;
}
#if defined(TICKY_TICKY)
// Post ticky counter sample.
// We do this at the end of execution since tickers are registered in the
// course of program execution.
if (performTickySample) {
emitTickyCounterSamples();
performTickySample = false;
}
#endif
// send exceptions to any threads which were about to die
RELEASE_SM_LOCK;
resurrectThreads(resurrected_threads);
......
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