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Pgindent run before 9.1 beta2.

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This commit is contained in:
Bruce Momjian
2011-06-09 14:32:50 -04:00
parent adf43b2b36
commit 6560407c7d
92 changed files with 644 additions and 620 deletions
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30
src/backend/commands/vacuum.c
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@@ -459,7 +459,7 @@ vacuum_set_xid_limits(int freeze_min_age,
* If we scanned the whole relation then we should just use the count of
* live tuples seen; but if we did not, we should not trust the count
* unreservedly, especially not in VACUUM, which may have scanned a quite
* nonrandom subset of the table. When we have only partial information,
* nonrandom subset of the table. When we have only partial information,
* we take the old value of pg_class.reltuples as a measurement of the
* tuple density in the unscanned pages.
*
@@ -471,7 +471,7 @@ vac_estimate_reltuples(Relation relation, bool is_analyze,
BlockNumber scanned_pages,
double scanned_tuples)
{
BlockNumber old_rel_pages = relation->rd_rel->relpages;
BlockNumber old_rel_pages = relation->rd_rel->relpages;
double old_rel_tuples = relation->rd_rel->reltuples;
double old_density;
double new_density;
@@ -483,8 +483,8 @@ vac_estimate_reltuples(Relation relation, bool is_analyze,
return scanned_tuples;
/*
* If scanned_pages is zero but total_pages isn't, keep the existing
* value of reltuples.
* If scanned_pages is zero but total_pages isn't, keep the existing value
* of reltuples.
*/
if (scanned_pages == 0)
return old_rel_tuples;
@@ -498,23 +498,23 @@ vac_estimate_reltuples(Relation relation, bool is_analyze,
/*
* Okay, we've covered the corner cases. The normal calculation is to
* convert the old measurement to a density (tuples per page), then
* update the density using an exponential-moving-average approach,
* and finally compute reltuples as updated_density * total_pages.
* convert the old measurement to a density (tuples per page), then update
* the density using an exponential-moving-average approach, and finally
* compute reltuples as updated_density * total_pages.
*
* For ANALYZE, the moving average multiplier is just the fraction of
* the table's pages we scanned. This is equivalent to assuming
* that the tuple density in the unscanned pages didn't change. Of
* course, it probably did, if the new density measurement is different.
* But over repeated cycles, the value of reltuples will converge towards
* the correct value, if repeated measurements show the same new density.
* For ANALYZE, the moving average multiplier is just the fraction of the
* table's pages we scanned. This is equivalent to assuming that the
* tuple density in the unscanned pages didn't change. Of course, it
* probably did, if the new density measurement is different. But over
* repeated cycles, the value of reltuples will converge towards the
* correct value, if repeated measurements show the same new density.
*
* For VACUUM, the situation is a bit different: we have looked at a
* nonrandom sample of pages, but we know for certain that the pages we
* didn't look at are precisely the ones that haven't changed lately.
* Thus, there is a reasonable argument for doing exactly the same thing
* as for the ANALYZE case, that is use the old density measurement as
* the value for the unscanned pages.
* as for the ANALYZE case, that is use the old density measurement as the
* value for the unscanned pages.
*
* This logic could probably use further refinement.
*/