Re: Indexing dynamics in MySQL Community Edition 5.1.34

2009-06-27 Thread Simon J Mudd
mo...@fastmail.fm (mos) writes: At 12:37 AM 6/25/2009, you wrote: ... my.cnf based on my-huge.cnf, expanding key_buffer to 8G, myisam_sort_buffer_size to 256M, and putting tmpdir on the fiber channel disk. You mean key_buffer_size don't you and not key_buffer? If you are using

Re: Indexing dynamics in MySQL Community Edition 5.1.34

2009-06-27 Thread Mike Spreitzer
Yes, all the indices are added in one ALTER TABLE statement. Thursday's incarnation took about 1.5 hours, on a table created from about 8 GB of CSV. Today's has already taken over 8 hours, on a table created from about 22 GB of data. The logarithm of 22 GB is about 24/23 of the logarithm of

Re: Indexing dynamics in MySQL Community Edition 5.1.34

2009-06-27 Thread Mike Spreitzer
Today's instance finished shortly after I sent the email below. BTW, here are some specifics on the table (which uses MyISAM). Thursday's instance has 11 GB of data and 0.78 GB of index. Today's instance has 26 GB of data and 1.8 GB of index. Thanks, Mike Spreitzer Mike

very strange performance issue

2009-06-27 Thread Chris Kantarjiev
I'm working in an environment where I have two similar servers, one running production the other for development. They're not very dissimilar - both run 4.1.20-log, both run CentOS 4. The development server has a cut-down snapshot of the production database, and it's where we ... well, develop

Re: very strange performance issue

2009-06-27 Thread Chris Kantarjiev
Perhaps some clues here: I started taking the problem query apart to see what slows things down. I found a culprit, but I don't understand: mysql select count(*) from Crumb where customer_id=380 and Actual_Time BETWEEN '2009-06-01 00:00' AND '2009-06-02 00:00' and ErrorCode = 0; +--+ |

Re: very strange performance issue

2009-06-27 Thread Chris Kantarjiev
Andrew Carlson said: I know this is basic, but check that you recreated the indexes after you reloaded the snapshot. That has bit me before. I used myisamchk -r on the large table, and it has made a huge difference. I had used myisamchk before to check the table and got no complaints.

Re: Indexing dynamics in MySQL Community Edition 5.1.34

2009-06-27 Thread Todd Lyons
On Sat, Jun 27, 2009 at 7:03 AM, Mike Spreitzermspre...@us.ibm.com wrote: Today's instance finished shortly after I sent the email below.  BTW, here are some specifics on the table (which uses MyISAM).  Thursday's instance has 11 GB of data and 0.78 GB of index.  Today's instance has 26 GB of