Greetings all, I have a question regarding the fsync data corruption bug that was introduced in 2.4.20 when using data=journal. I have patched the 2.4.20 kernel with the 3 sync patches available from zip.com.au, and I am wondering if with these patches the "bug" still exists: sync_fs.patch sync_fs-fix.patch sync_fs-fix-2.patch In addition the following two patches have also been applied: ext3-use-after-free.patch ext3-scheduling-storm.patch Also, from what I understand 'data=journal' would be beneficial in cases where data is being written to and read from disks constantly. Would it be advised to use this data mode in a webserver environment in which there are many virtual hosts(provided the above bug was fixed with the patches)? One last thing is that I have come up with the below bdflush settings based on the filesystem/proc.txt kernel documentation. Combined with data=journal or data=ordered would these settings have any adverse effects on the system? ---- nfract Percentage of buffer cache dirty to activate bdflush ndirty Maximum number of dirty blocks to write out per wake-cycle nrefill Number of clean buffers to try to obtain each time we call refill nref_dirt buffer threshold for activating bdflush when trying to refill buffers. dummy Unused age_buffer Time for normal buffer to age before we flush it age_super Time for superblock to age before we flush it dummy Unused dummy Unused ----- Default bdflush settings: 30 500 0 0 500 3000 60 20 0 Settings offered on this list 90 500 0 0 600000 600000 95 20 0 Would the above settings not crush the server? Those settings are flushing fs metadata about once per second, and data blocks every 600 seconds. This is what I have come up with: 20 300 0 0 0 500 60 0 0 I'm doing some testing of these values, both with journal and ordered data modes. If anyone has any real-world performance gains/losses with any elevator/bdflush settings, I would greatly appreciate hearing about them. Any other advice is welcome. TIA, -Mark _______________________________________________ Ext3-users@redhat.com https://listman.redhat.com/mailman/listinfo/ext3-users
