[zfs-discuss] Monitoring disk seeks

2011-05-19 Thread Sašo Kiselkov
Hi all, I'd like to ask whether there is a way to monitor disk seeks. I have an application where many concurrent readers (>50) sequentially read a large dataset (>10T) at a fairly low speed (8-10 Mbit/s). I can monitor read/write ops using iostat, but that doesn't tell me how contiguous the data

Re: [zfs-discuss] Monitoring disk seeks

2011-05-19 Thread Jim Klimov
I am not sure you can monitor actual mechanical seeks short of debugging and interrogating the HDD firmware - because it is the last responsible logic in the chain of caching, queuing and issuing actual commands to the disk heads. For example, a long logical IO spanning several cylinders would pr

Re: [zfs-discuss] Monitoring disk seeks

2011-05-19 Thread Jim Klimov
2011-05-19 17:00, Jim Klimov пишет: I am not sure you can monitor actual mechanical seeks short of debugging and interrogating the HDD firmware - because it is the last responsible logic in the chain of caching, queuing and issuing actual commands to the disk heads. For example, a long logical I

Re: [zfs-discuss] Monitoring disk seeks

2011-05-19 Thread Tomas Ögren
On 19 May, 2011 - Sa??o Kiselkov sent me these 0,6K bytes: > Hi all, > > I'd like to ask whether there is a way to monitor disk seeks. I have an > application where many concurrent readers (>50) sequentially read a > large dataset (>10T) at a fairly low speed (8-10 Mbit/s). I can monitor > read/w

Re: [zfs-discuss] Monitoring disk seeks

2011-05-19 Thread Sašo Kiselkov
On 05/19/2011 03:35 PM, Tomas Ögren wrote: > On 19 May, 2011 - Sa??o Kiselkov sent me these 0,6K bytes: > >> Hi all, >> >> I'd like to ask whether there is a way to monitor disk seeks. I have an >> application where many concurrent readers (>50) sequentially read a >> large dataset (>10T) at a fai

Re: [zfs-discuss] Monitoring disk seeks

2011-05-19 Thread Brandon High
On Thu, May 19, 2011 at 5:35 AM, Sašo Kiselkov wrote: > I'd like to ask whether there is a way to monitor disk seeks. I have an > application where many concurrent readers (>50) sequentially read a > large dataset (>10T) at a fairly low speed (8-10 Mbit/s). I can monitor > read/write ops using ios

Re: [zfs-discuss] Monitoring disk seeks

2011-05-19 Thread Richard Elling
On May 19, 2011, at 5:35 AM, Sašo Kiselkov wrote: > Hi all, > > I'd like to ask whether there is a way to monitor disk seeks. I have an > application where many concurrent readers (>50) sequentially read a > large dataset (>10T) at a fairly low speed (8-10 Mbit/s). I can monitor > read/write ops

Re: [zfs-discuss] Monitoring disk seeks

2011-05-20 Thread Sašo Kiselkov
On 05/19/2011 07:47 PM, Richard Elling wrote: > On May 19, 2011, at 5:35 AM, Sašo Kiselkov wrote: > >> Hi all, >> >> I'd like to ask whether there is a way to monitor disk seeks. I have an >> application where many concurrent readers (>50) sequentially read a >> large dataset (>10T) at a fairly lo

Re: [zfs-discuss] Monitoring disk seeks

2011-05-24 Thread a . smith
Hi, see the seeksize script on this URL: http://prefetch.net/articles/solaris.dtracetopten.html Not used it but looks neat! cheers Andy. ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-di

Re: [zfs-discuss] Monitoring disk seeks

2011-05-24 Thread Sašo Kiselkov
On 05/24/2011 03:08 PM, a.sm...@ukgrid.net wrote: > Hi, > > see the seeksize script on this URL: > > http://prefetch.net/articles/solaris.dtracetopten.html > > Not used it but looks neat! > > cheers Andy. I already did and it does the job just fine. Thank you for your kind suggestion. BR, -