Setting CentOS 5.5 up to cache the disk more heavily for wri

[j0rd0n420]

Thanks John.

[Edge100x]

If you're seeing problems due to occasional large spikes in disk access and you still have free memory available, try telling Linux to cache more of those writes in memory before it forces them to be flushed to disk and stalls applications.

A high dirty_ratio will allow more memory to be used for the write cache, and a low dirty_background_ratio will ensure that it gets written to disk regularly in the background, so that it doesn't stack up:

Code: Select all

echo 80 > /proc/sys/vm/dirty_ratio
echo 5 > /proc/sys/vm/dirty_background_ratio

Note that if you are seeing constant decently high amounts of disk writes, these settings probably won't help, and may even hurt. The same is true if you have a read-heavy application; with lots of reads, it's good to keep the write cache small.

[j0rd0n420]

Do I just enter those into the terminal?

[Edge100x]

Yes, that's correct.

Also, if you don't have much RAM free, they may not make a very big difference for you.

[j0rd0n420]

Hmmm...I'll prolly just keep it as is and upgrade my VPS next month.

[Jesse]

Hmmm...I'll prolly just keep it as is and upgrade my VPS next month.

You can upgrade it whenever, because its pro-rated. So whatever you already paid goes into the upgraded servers cost. NFo Ftw.

[j0rd0n420]

I didn't have the funds to do that till the beginning of the month though.