MySQL Bugs: #50595: funcs_1.myisam_views takes longer time on 6.0 branch than 5.1 branch

Bug #50595	funcs_1.myisam_views takes longer time on 6.0 branch than 5.1 branch
Submitted:	25 Jan 2010 16:28	Modified:	8 Jan 2011 16:32
Reporter:	Alexander Nozdrin	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Optimizer	Severity:	S3 (Non-critical)
Version:	6.0	OS:	Solaris (Solaris 10 sparc32 debug, sparc64)
Assigned to:	Guilhem Bichot	CPU Architecture:	Any
Tags:	experimental, pb2, regression, test failure

File:	Maximum allowed size is 50MB.
Description:
Privacy:

If the data you need to attach is more than 50MB, you should create a compressed archive of the data, split it to 50MB chunks, and upload each of them as a separate attachment.

To split a large file:

On *nix platforms use the split command e.g. split -b 50MB <my_large_archive> <my_split_archive_prefix>
On windows use WinZip or a similar utility to split the large file

same as views_master.inc but with #ZZ marks marking the 10 slow queries

Attachment: views_master.inc.with_ZZ (application/octet-stream, text), 140.74 KiB.

reduced testcase, SELECT and EXPLAIN each take 0.5 secs more in 6.0

Attachment: bug.test (application/octet-stream, text), 3.18 KiB.

test and result which have been used for finding the regression source

Attachment: bzrfind_test.tar.gz (application/x-gzip, text), 1.01 KiB.

mysqldump-made script to create tables of benchmark

Attachment: benchmark_tables_dump.sql.txt.gz (application/x-gzip, text), 2.57 KiB.

patch for sql_select.cc to have timings

Attachment: timing_patch.txt (text/plain), 730 bytes.