diff options
Diffstat (limited to 'src/backend/executor/instrument.c')
| -rw-r--r-- | src/backend/executor/instrument.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/src/backend/executor/instrument.c b/src/backend/executor/instrument.c index bf9bf12ab6..9d30200ab3 100644 --- a/src/backend/executor/instrument.c +++ b/src/backend/executor/instrument.c @@ -22,6 +22,7 @@ BufferUsage pgBufferUsage; static void BufferUsageAccumDiff(BufferUsage *dst, const BufferUsage *add, const BufferUsage *sub); + /* Allocate new instrumentation structure(s) */ Instrumentation * InstrAlloc(int n, int instrument_options) @@ -31,13 +32,14 @@ InstrAlloc(int n, int instrument_options) /* timer is always required for now */ Assert(instrument_options & INSTRUMENT_TIMER); + /* initialize all fields to zeroes, then modify as needed */ instr = palloc0(n * sizeof(Instrumentation)); if (instrument_options & INSTRUMENT_BUFFERS) { int i; for (i = 0; i < n; i++) - instr[i].needs_bufusage = true; + instr[i].need_bufusage = true; } return instr; @@ -52,8 +54,8 @@ InstrStartNode(Instrumentation *instr) else elog(DEBUG2, "InstrStartNode called twice in a row"); - /* initialize buffer usage per plan node */ - if (instr->needs_bufusage) + /* save buffer usage totals at node entry, if needed */ + if (instr->need_bufusage) instr->bufusage_start = pgBufferUsage; } @@ -77,8 +79,8 @@ InstrStopNode(Instrumentation *instr, double nTuples) INSTR_TIME_SET_ZERO(instr->starttime); - /* Adds delta of buffer usage to node's count. */ - if (instr->needs_bufusage) + /* Add delta of buffer usage since entry to node's totals */ + if (instr->need_bufusage) BufferUsageAccumDiff(&instr->bufusage, &pgBufferUsage, &instr->bufusage_start); @@ -119,12 +121,12 @@ InstrEndLoop(Instrumentation *instr) instr->tuplecount = 0; } +/* dst += add - sub */ static void BufferUsageAccumDiff(BufferUsage *dst, const BufferUsage *add, const BufferUsage *sub) { - /* dst += add - sub */ dst->shared_blks_hit += add->shared_blks_hit - sub->shared_blks_hit; dst->shared_blks_read += add->shared_blks_read - sub->shared_blks_read; dst->shared_blks_written += add->shared_blks_written - sub->shared_blks_written; |