When i changed to delaylog option my database performance increased, so how i have 2 databases one master another slave, i can keep it. If i have problem on my filesystem, i'll need to changed the slave to master and recover my master. Thanks all. On Tue, Sep 14, 2010 at 5:03 PM, Stan Hoeppner <stan@xxxxxxxxxxxxxxxxx> wrote: > Arkadiusz Miskiewicz put forth on 9/14/2010 2:06 PM: >> On Tuesday 14 of September 2010, Fabricio Archanjo wrote: >>> Hey all, >>> >>> I just trying delaylog in my server that has a mysql database. When >>> i monted my /var/lib/mysql with delaylog option, it showed me: >>> "Enabling EXPERIMENTAL delayed logging feature - use at your own >>> risk". Ok, i know it's experimental, but what kind of problem could i >>> have using delaylog? >> >> ... and what problems in case of system hang or power loss when compared to >> nodelaylog mode? > > This was covered in prior posts IIRC. Delaylog holds more write > transactions in memory in an effort to decrease the amount of disk I/O > and optimize write patterns. The more blocks waiting in the in memory > log, the more data will be lost due to power outage, controller/disk > failure, storage HBA/network failure (iSCSI/FC), kernel panics, etc. > > Same failure modes as before, but with potentially greater loss of > data--unless there is an undiscovered bug that can wreck the entire > filesystem. ;) Which I believe is the reason for the "experimental" > boilerplate. > > -- > Stan > > _______________________________________________ > xfs mailing list > xfs@xxxxxxxxxxx > http://oss.sgi.com/mailman/listinfo/xfs > _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
