A 7.5 is probably fine and can still beat it as it is going to be the speed of writing not seeking(and I am not sure if they spec hard drives with a write time when not seeking….not sure). Remember that drives are rated on how fast they spin…this disk should not be spinning a lot(in theory)…it is always writing.
Even on a read, it would do one seek and then do a very long sequential read(and I think that only happens on startup anyways). Later, Dean From: Darvin Denmian <darvin.denm...@gmail.com<mailto:darvin.denm...@gmail.com>> Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> Date: Wednesday, August 8, 2012 7:16 AM To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> Subject: Re: Use of SSD for commitlog Thanks for your reply Dean, considering your reply.... maybe I use a 15k RPM SCSI Disk, I think it'll perform better than a SSD disk. On Wed, Aug 8, 2012 at 10:01 AM, Hiller, Dean <dean.hil...@nrel.gov<mailto:dean.hil...@nrel.gov>> wrote: Probably not since it is sequential writes….(ie. Seek performance is the big hit and if it is sequential it should not be seeking and is about just as fast as an SSD in theory). In practice, I have not measure the performance of one vs. the other though…that I always the best way to go.(you could write a micro benchmark test with warmup writes and then stream writes to and see how it does without cassandra). Dean From: Darvin Denmian <darvin.denm...@gmail.com<mailto:darvin.denm...@gmail.com><mailto:darvin.denm...@gmail.com<mailto:darvin.denm...@gmail.com>>> Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>> Date: Tuesday, August 7, 2012 8:34 PM To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>> Subject: Use of SSD for commitlog Hi, Can somebody tell me if is there some benefit in use SSD Disks for commitlog? THanks!
