similar to: Measuring memory bandwidth utilization

Hello, When approaching hosting providers for services, the first question many of them asked us was about the amount of IOPS the disk system should support. While we stress-tested our service, we recorded between 4000 and 6000 "merged io operations per second" as seen in "iostat -x" and collectd (varies between the different components of the system, we have a few such

On 2/2/2016 5:34 PM, Benjamin Smith wrote: > I'd like to know what the cause of a particular DB server's slowdown might be. > We've ruled out IOPs for the disks (~ 20%) and raw CPU load (top shows perhaps > 1/2 of cores busy, but the system slows to a crawl. > > We're suspecting that we're simply running out of memory bandwidth but have no > way to confirm

On 02/02/2016 05:34 PM, Benjamin Smith wrote: > We've ruled out IOPs for the disks (~ 20%) How did you measure that? What filesystem are you using? What is the disk / array configuration? Which database? If you run "iostat -x 2" what does a representative summary look like? > and raw CPU load (top shows perhaps > 1/2 of cores busy, but the system slows to a crawl.

I have several X4540 Thor systems with one large zpool that replicate data to a backup host via zfs send/recv. The process works quite well when there is little to no usage on the source systems. However when the source systems are under usage replication slows down to a near crawl. Without load replication streams along usually near 1 Gbps but drops down to anywhere between 0 - 5000

Can anybody tell me how to measure the raw performance of a new system I''m putting together? I''d like to know what it''s capable of in terms of IOPS and raw throughput to the disks. I''ve seen Richard''s raidoptimiser program, but I''ve only seen results for random read iops performance, and I''m particularly interested in write

Hi!We''re trying to pinpoint our performance issues and we could use all the help to community can provide. We''re running the latest version of Nexenta on a pretty powerful machine (4x Xeon 7550, 256GB RAM, 12x 100GB Samsung SSDs for the cache, 50GB Samsung SSD for the ZIL, 10GbE on a dedicated switch, 11x pairs of 15K HDDs for the pool). We''re connecting a single Linux

I figure this group will know better than any other I have contact with, is 700-800 I/Ops reasonable for a 7200 RPM SATA drive (1 TB Sun badged Seagate ST31000N in a J4400) ? I have a resilver running and am seeing about 700-800 writes/sec. on the hot spare as it resilvers. There is no other I/O activity on this box, as this is a remote replication target for production data. I have a the

Hi, Seeing a drop-off in iops when more vcpu''s are added:- 3.8.2 kernel/xen-4.2.1/single domU/LVM backend/8GB RAM domU/2GB RAM dom0 dom0_max_vcpus=2 dom0_vcpus_pin domU 8 cores fio result 145k iops domU 10 cores fio result 99k iops domU 12 cores fio result 89k iops domU 14 cores fio result 81k iops ioping . -c 3 4096 bytes from . (ext4 /dev/xvda1): request=1 time=0.1 ms 4096 bytes

I know this topic has been discussed many times... but what the hell makes zpool resilvering so slow? I''m running OpenSolaris 2009.06. I have had a large number of problematic disks due to a bad production batch, leading me to resilver quite a few times, progressively replacing each disk as it dies (and now preemptively removing disks.) My complaint is that resilvering ends up

Hey, folks, Sometimes my workstation bogs down... slows to a crawl. Using gkrellm, it's obvious the CPU is the laggard. The top utility confirms: the load average gets up over 4 at times. But this occurs when cpu stepping pegs the speed at 600MHz. This processor is capable of 1.5GHz and when it's allowed to run at that speed, the load average is under 2, which is fine. So the

Hi people... Here we use Xen 4 with Debian Lenny... We''re using kernel 2.6.31.13 pvops... As a storage system, we use AoE devices... So, we installed VM''s on AoE partition... The "NAS" server is a Intel based baremetal with SATA hard disc... However, sometime I feeling that VM''s is so slow... Also, all VM has GPLPV drivers installed... So, I am thing about

hello, is there any way can monitor every lvm parition i/o so we can know which domU hit the hard disk i/o . thanks _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users

Dtrace and Performance Teams, I have the following IO Performance Specific Questions (and I''m already savy with the lockstat and pre-dtrace utilities for performance analysis.. but in need of details regarding specifying IO bottlenecks @ the controller or IO bus..) : **Q.A*> Determining IO Saturation bottlenecks ( */.. beyond service times and kernel contention.. )/ I''m

Hi, folks, I''m attempting to run an e-mail server on Xen. The e-mail system is Novell GroupWise, and it serves about 250 users. The disk volume for the e-mail is on my SAN, and I''ve attached the FC LUN to my Xen host, then used the "phy:/dev..." method to forward the disk through to the domU. I''m running into an issue with high I/O wait on the box (~250%)

I''m not a windows person, so I am hoping someone can help me with this... I''ve just installed a Windows 2003 Server VM and I would like to make sure that the average disk IO wait is acceptable. In Linux and other *nixes I would normally use sar or iostat for this. I have found perfmon in windows. Will this give me the numbers I need? Thanks, Matt.

What is the best way to tell if your bound by the number of individual operations per second / random io? "zpool iostat" has an "operations" column but this doesn''t really tell me if my disks are saturated. Traditional "iostat" doesn''t seem to be the greatest place to look when utilizing zfs. Thanks, Chris -------------- next part -------------- An

Under Solaris 10 on a 4 core Sun Ultra 40 with 20GB RAM, I am setting up a Sun StorageTek 2540 with 12 300GB 15K RPM SAS drives and connected via load-shared 4Gbit FC links. This week I have tried many different configurations, using firmware managed RAID, ZFS managed RAID, and with the controller cache enabled or disabled. My objective is to obtain the best single-file write performance.

Folks I use "yum list installed" to determine if a package has been installed. In particular, I was interested in the "man" program, installed with the command "yum install man". In Centos6, if I look at the results, I see that "man" was installed. This is good. In Centos7, if I look at the results, I see that "man-db" was installed. This

Running a zpool scrub on our production pool is showing a scrub rate of about 400K/s. (When this pool was first set up we saw rates in the MB/s range during a scrub). Both zpool iostat and an iostat -Xn show lots of idle disk times, no above average service times, no abnormally high busy percentages. Load on the box is .59. 8 x 3GHz, 32GB ram, 96 spindles arranged into raidz zdevs on OI 147.

Hi ! I have a server (Centos 5) that is using a pair of SAS drives to store the data. (Mail server) They are on an adaptec raid controler with a battery backup and write back cache active. >From time to time, I have sever peak io to those data disks (> 400 to 500 iops, > 70 to 100 megs/sec). With iostat, I find that it's almost a write i/o problem. How can I find to which files