[ltt-dev] [PATCH] Fixing bugs in cluster synchronisation for accuracy algorithm
Mathieu Desnoyers
compudj at krystal.dyndns.org
Mon Sep 13 16:39:33 EDT 2010
* masoume.jabbarifar at polymtl.ca (masoume.jabbarifar at polymtl.ca) wrote:
> From: Masoume Jabbarifar <masoume.jabbarifar at polymtl.ca>
>
Can you document the change in the patch header ?
Also, please CC Benjamin on these changes. I'd like him to have a look
at them if he has time.
> ---
> lttv/lttv/sync/data_structures.h | 2 +-
> lttv/lttv/sync/factor_reduction_accuracy.c | 15 ++++++++++++---
> lttv/lttv/sync/sync_chain_lttv.c | 18 ++++++++++++------
> lttv/lttv/sync/sync_chain_unittest.c | 9 ++++++---
> 4 files changed, 31 insertions(+), 13 deletions(-)
>
> diff --git a/lttv/lttv/sync/data_structures.h b/lttv/lttv/sync/data_structures.h
> index 627286c..2206455 100644
> --- a/lttv/lttv/sync/data_structures.h
> +++ b/lttv/lttv/sync/data_structures.h
> @@ -131,7 +131,7 @@ typedef struct
> * synchronization */
> typedef struct
> {
> - double drift, offset;
> + double drift, offset, accuracyToRefNode;
Hrm, I see that the sync code use a different coding style than the rest
of lttv. *sight* OK then.
For your information, the rest of lttv uses lower cases for variable
identifiers, and UpperCase for type identifiers. It also uses
lower_case_with_underscore() for function names.
> } Factors;
>
> // Correction factors between trace pairs, to be used for reduction
> diff --git a/lttv/lttv/sync/factor_reduction_accuracy.c b/lttv/lttv/sync/factor_reduction_accuracy.c
> index a63dae7..bf0546b 100644
> --- a/lttv/lttv/sync/factor_reduction_accuracy.c
> +++ b/lttv/lttv/sync/factor_reduction_accuracy.c
> @@ -415,12 +415,19 @@ static void getFactors(AllFactors* const allFactors, unsigned int** const
> unsigned int reference;
> PairFactors** const pairFactors= allFactors->pairFactors;
>
> - reference= references[traceNum];
> -
> + if (traceNum == references[traceNum])
> + {
> + reference=traceNum;
> + }
> + else
> + {
> + reference = predecessors[references[traceNum]][traceNum];
> + }
> if (reference == traceNum)
> {
> factors->offset= 0.;
> factors->drift= 1.;
> + factors->accuracyToRefNode= 0.;
> }
> else
> {
> @@ -428,6 +435,8 @@ static void getFactors(AllFactors* const allFactors, unsigned int** const
>
> getFactors(allFactors, predecessors, references,
> predecessors[reference][traceNum], &previousVertexFactors);
> + factors->accuracyToRefNode =
> + pairFactors[reference][traceNum].accuracy+ pairFactors[traceNum][reference].accuracy + previousVertexFactors.accuracyToRefNode;
>
> /* Convert the time from traceNum to reference;
> * pairFactors[row][col] converts the time from col to row, invert the
> @@ -452,7 +461,7 @@ static void getFactors(AllFactors* const allFactors, unsigned int** const
> }
> else
> {
> - g_assert_not_reached();
> + //g_assert_not_reached();
Why commenting this ? This assertion was probably there for a reason.
Shutting up assertions without proper comments is usually a bad
practice, as assertions are our safety nets.
> }
> }
> }
> diff --git a/lttv/lttv/sync/sync_chain_lttv.c b/lttv/lttv/sync/sync_chain_lttv.c
> index 95bef44..20ed111 100644
> --- a/lttv/lttv/sync/sync_chain_lttv.c
> +++ b/lttv/lttv/sync/sync_chain_lttv.c
> @@ -218,6 +218,7 @@ bool syncTraceset(LttvTracesetContext* const traceSetContext)
> double minOffset, minDrift;
> unsigned int refFreqTrace;
> int retval;
> + double sumAccuracy;
>
> if (!optionSync.present)
> {
> @@ -370,8 +371,6 @@ bool syncTraceset(LttvTracesetContext* const traceSetContext)
> t->drift * t->start_tsc + t->offset));
> }
>
> - g_array_free(factors, TRUE);
> -
> lttv_traceset_context_compute_time_span(traceSetContext,
> &traceSetContext->time_span);
>
> @@ -395,21 +394,28 @@ bool syncTraceset(LttvTracesetContext* const traceSetContext)
> if (!optionSyncNull.present && optionSyncStats.present)
> {
> printStats(syncState);
> -
> + sumAccuracy = 0;
= 0.;
> printf("Resulting synchronization factors:\n");
> for (i= 0; i < syncState->traceNb; i++)
> {
> LttTrace* t;
> + Factors* traceFactors;
>
> t= traceSetContext->traces[i]->t;
> -
> - printf("\ttrace %u drift= %g offset= %g (%f) start time= %ld.%09ld\n",
> + traceFactors= &g_array_index(factors, Factors, i);
> +
> + printf("\ttrace %u drift= %g offset= %g (%f) start time= %ld.%09ld accuracyToRefNode= %g\n",
> i, t->drift, t->offset, (double) tsc_to_uint64(t->freq_scale,
> t->start_freq, t->offset) / NANOSECONDS_PER_SECOND,
> t->start_time_from_tsc.tv_sec,
> - t->start_time_from_tsc.tv_nsec);
> + t->start_time_from_tsc.tv_nsec,traceFactors->accuracyToRefNode);
> + sumAccuracy += traceFactors->accuracyToRefNode;
> +
> }
> }
> + printf("Total accuracy (0.0 is the best): %g\n",sumAccuracy);
> +
> + g_array_free(factors, TRUE);
>
> syncState->processingModule->destroyProcessing(syncState);
> if (syncState->matchingModule != NULL)
> diff --git a/lttv/lttv/sync/sync_chain_unittest.c b/lttv/lttv/sync/sync_chain_unittest.c
> index 40302a0..d59eb09 100644
> --- a/lttv/lttv/sync/sync_chain_unittest.c
> +++ b/lttv/lttv/sync/sync_chain_unittest.c
> @@ -114,6 +114,7 @@ int main(const int argc, char* const argv[])
> GString* analysisModulesNames;
> GString* reductionModulesNames;
> unsigned int id;
> + double sumAccuracy;
> AllFactors* allFactors;
>
> /*
> @@ -266,15 +267,17 @@ int main(const int argc, char* const argv[])
> unsigned int i;
>
> printStats(syncState);
> -
> + sumAccuracy = 0;
= 0.;
Thanks,
Mathieu
> printf("Resulting synchronization factors:\n");
> for (i= 0; i < factors->len; i++)
> {
> Factors* traceFactors= &g_array_index(factors, Factors, i);
> - printf("\ttrace %u drift= %g offset= %g\n", i,
> - traceFactors->drift, traceFactors->offset);
> + printf("\ttrace %u drift= %g offset= %g accuracyToRefNode= %g\n", i,
> + traceFactors->drift, traceFactors->offset, traceFactors->accuracyToRefNode);
> + sumAccuracy += traceFactors->accuracyToRefNode;
> }
> }
> + printf("Total accuracy (0.0 is the best): %g\n",sumAccuracy);
>
> // Destroy modules and clean up
> syncState->processingModule->destroyProcessing(syncState);
> --
> 1.6.0.4
>
>
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>
--
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
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