Frequent corruption of Post and Thread ISM files

[Kenn]

Earlier we were having problems with session.ISM corrupting all the time, but after following directions on one of these boards, and recreating that table, that stopped happening. Now however, we are getting very frequent corruption errors in post and threads tables.

When this happens, one our more of the forums lose all but a few threads until I repair the database with isamchk (-r or -o options)


Here's the output of an isamchk post.ISM command


isamchk post.ISM
Checking ISAM file: post.ISM
Data records: 174937 Deleted blocks: 0
- check file-size
- check delete-chain
- check index reference
- check data record references index: 1
- check data record references index: 2
isamchk: error: Found key at page 2670592 that points to record outside datafile
- check record links
isamchk: error: Keypointers and records dosen't match
ISAM-table 'post.ISM' is corrupted
Fix it using switch "-r" or "-o"


After running isamchk -r, this error doesn't show up, and all the missing threads come back, but it generally happens again within a couple of hours.

Does anyone have any suggestions about what might be causing this? I don't think it is constrained to really active times, and the server and mysql seem to be staying up through the error.

[shashi]

Well,you haven't mentioned the mysql errors, but there are a few things you might check.

1. you may be running out of file handles (max open files) as per your shell limits or your kernel limits. I think it is first one, if it is. and that can be set correct if you modify the safe_mysqld script (there is a line about ulimit -n 256 or so, uncomment those 3-4 lines.
You may also want to increase table_cache (as startup option to safe_mysqld) to something like 256 or so if you can afford.

2. How big is the file? Has it grown too large?

3. Did fsck give any errors?
I have had some fsck problems, I am not able to figure out what could cause that. I have pretty new SCSI harddrives from seagate.

Hope that helps.

Shashi

[j(",)y]

How do I handle the error "ERROR 1030: Got error 127 from table handler.

When i click on the thread, this error shows (invoking showthread.php3)

Warning: MySQL: Unable to save result set in forums/admin/db_mysql.php3 on line 93

There seems to have been a slight problem with the database. Please try again by pressing the refresh button in your browser.

An E-Mail has been dispatched to our Technical Staff, who you can also contact if the problem persists.

We apologise for any inconvenience.