Disk Tuning for large caches.

[Vikram <mv...@yahoo.com>]

Hi,

I wanted to know if there were any informal rules to configure disk caching for ATS for optimal performance. The documentation for this is a little bit lacking :) http://trafficserver.readthedocs.org/en/latest/admin/performance-tuning.en.html

What i have been able to scrounge up so far is:

1. Raw disk partitions are better.
2. Across multiple disks, partitions are recommended to be the same size, and each disk should have the same number of partitions

My setup will have about 10 HDDs, each of 3TB size.  I am planning on giving 1TB from each disk as a RAW partition to ATS, which I presume would be a reasonable set up. Are there any other back of the thumb rules (like maybe creating the raw partition in the center of the physical disk to reduce seek times)? Also, would there be a quick and dirty way to calculate the amount of RAM cache I should allocate, or should I go with the default setting of 1MB RAM Cache per 1 GB of Cache?

I will be doing a round of tests with different settings for my particular use case, but I wanted to start off with a reasonable approximation of the optimal setup.

Any info will help!

Thanks,
Vikram