Does concurrent_reads relate to number of drives in RAID0?

Hello, in the instructions, I need to link concurrent_reads to number of drives. Is this related to number of physical drives that I have in my RAID0, or something else? -- View this message in context:

Re: Does concurrent_reads relate to number of drives in RAID0?

The comment in the example config file next to that setting explains it more fully, but something like 16 * number of drives is a reasonable setting for readers. Writers should be a multiple of the number of cores. In addition, if you're running on Linux in a situation where you're trying to

Re: Does concurrent_reads relate to number of drives in RAID0?

Thanks to all for replying, but frankly I didn't get the answer I wanted. Does the number of disks apply to number of spindles in RAID0? Or something else like a separate disk for commitlog and for data? -- View this message in context:

Re: Does concurrent_reads relate to number of drives in RAID0?

Thanks to all for replying, but frankly I didn't get the answer I wanted. Does the number of disks apply to number of spindles in RAID0? Or something else like a separate disk for commitlog and for data? The number of actual disks (spindles) in the device on which your sstables are on (not the

Re: Does concurrent_reads relate to number of drives in RAID0?

The reason for this is that you want to be able to saturate your storage subsystem, and that means keeping all spindles working at all times and efficiently. This is accomplished by ensuring you are able to sustain a sufficient queue depth (number of outstanding commands) on each device. This

Re: Does concurrent_reads relate to number of drives in RAID0?

Thanks Peter, I can see it better now. -- View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Does-concurrent-reads-relate-to-number-of-drives-in-RAID0-tp6182346p6183051.html Sent from the cassandra-u...@incubator.apache.org mailing list archive at

Re: Does concurrent_reads relate to number of drives in RAID0?

Where and how do I choose it? -- View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Does-concurrent-reads-relate-to-number-of-drives-in-RAID0-tp6182346p6183069.html Sent from the cassandra-u...@incubator.apache.org mailing list archive at Nabble.com.

Re: Does concurrent_reads relate to number of drives in RAID0?

Also when it comes to RAID controller there are other options like write policy, read policy, cache io/direct io. Is there any preference on which policies should be chosen? In our case: http://support.dell.com/support/edocs/software/svradmin/1.9/en/stormgmt/cntrls.html -- View this message in