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| author | Vasil Dimov <vasil.dimov@oracle.com> | 2011-09-09 10:07:24 +0300 |
|---|---|---|
| committer | Vasil Dimov <vasil.dimov@oracle.com> | 2011-09-09 10:07:24 +0300 |
| commit | 13fefeb04ade34418cd9d99aa93bffb69fdae27e (patch) | |
| tree | 9c5657d74bbc585ba30be7b3d61437d9b7162d60 | |
| parent | 8c545acd5367950d3d03590880781089040016e0 (diff) | |
| download | mariadb-git-13fefeb04ade34418cd9d99aa93bffb69fdae27e.tar.gz | |
Disable the prefetch code in the InnoDB internal SQL parser.
This change is a followup to
vasil.dimov@oracle.com-20110907145810-v98kldmho23vhhic
which triggered the usage of the prefetch and valgrind tests spat lots of
warnings.
The prefetch code will be removed.
Discussed with: Marko (over IM)
| -rw-r--r-- | storage/innodb_plugin/row/row0sel.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/storage/innodb_plugin/row/row0sel.c b/storage/innodb_plugin/row/row0sel.c index 241584eaa20..aa3f6283c4f 100644 --- a/storage/innodb_plugin/row/row0sel.c +++ b/storage/innodb_plugin/row/row0sel.c @@ -63,7 +63,13 @@ Created 12/19/1997 Heikki Tuuri /* Number of rows fetched, after which to start prefetching; MySQL interface has another parameter */ -#define SEL_PREFETCH_LIMIT 1 +/* The prefetch code in the internal SQL is disabled because it has probably +never been used and has been found to contain a memory leak and a bug of +accessing uninitialized memory. Some simple performance tests show that +disabling it makes no difference in performance. It will be removed, but +until the removal happens we disable it by setting SEL_PREFETCH_LIMIT to a +high value. */ +#define SEL_PREFETCH_LIMIT 1000000000 /* When a select has accessed about this many pages, it returns control back to que_run_threads: this is to allow canceling runaway queries */ |