search for: zfs_vdev_max_pending

We have a zpool made of 4 512g iscsi luns located on a network appliance. We are seeing poor read performance from the zfs pool. The release of solaris we are using is: Solaris 10 10/09 s10s_u8wos_08a SPARC The server itself is a T2000 I was wondering how we can tell if the zfs_vdev_max_pending setting is impeding read performance of the zfs pool? (The pool consists of lots of small files). And if it is impeding read performance, how do we go about finding a new value for this parameter? Of course I may misunderstand this parameter entirely and would be quite happy for an proper explana...

Under Solaris 10 u6 , No matter how I configured my ARECA 1261ML Raid card I got errors on all drives that result from SCSI timeout errors. yoda:~ # tail -f /var/adm/messages Jan 9 11:03:47 yoda.asc.edu scsi: [ID 107833 kern.notice] Requested Block: 239683776 Error Block: 239683776 Jan 9 11:03:47 yoda.asc.edu scsi: [ID 107833 kern.notice] Vendor: Seagate

...g a large file to the system results in 50 to 60 megs worth of transfer, and then a stall for five to ten seconds, then continuing. I''ve seen others complain about ZFS performance on the MegaRAID controllers, and I''ve tried some of the suggestions in those threads... dialing down zfs_vdev_max_pending (currently 35, I''ve tried 15 and even 4) and turning off prefetch, all via mdb -kw... it doesn''t seem to make a difference. Any suggestions as to where I can try to figure out what''s going on here? -- This message posted from opensolaris.org

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 all, just after sending a message to sunmanagers I realized that my question should rather have gone here. So sunmanagers please excus ethe double post: I have inherited a X4140 (8 SAS slots) and have just setup the system with Solaris 10 09. I first setup the system on a mirrored pool over the first two disks pool: rpool state: ONLINE scrub: none requested config: NAME

...s led to to the computer hanging within a minute ("vmstat 1" shows that free RAM plummets towards the zero mark). I''ve tried preparing the system tunables as well: :; echo "aok/W 1" | mdb -kw :; echo "zfs_recover/W 1" | mdb -kw and sometimes adding: :; echo zfs_vdev_max_pending/W0t5 | mdb -kw :; echo zfs_resilver_delay/W0t0 | mdb -kw :; echo zfs_resilver_min_time_ms/W0t20000 | mdb -kw :; echo zfs_txg_synctime/W0t1 | mdb -kw In this case I am not very hesitant to recreate the rpool and reinstall the OS - it was mostly needed to server the separate data pool. However this...

I was trying to simply test bandwidth that Solaris/ZFS (Nevada b63) can deliver from a drive, and doing this: dd if=(raw disk) of=/dev/null gives me around 80MB/s, while dd if=(file on ZFS) of=/dev/null gives me only 35MB/s!?. I am getting basically the same result whether it is single zfs drive, mirror or a stripe (I am testing with two Seagate 7200.10 320G drives hanging off the same interface

Dear All, It may be this not the correct mailing list, but I''m having a ZFS issue when a disk is failing. The system is a supermicro motherboard X8DTH-6F in a 4U chassis (SC847E1-R1400LPB) and an external SAS2 JBOD (SC847E16-RJBOD1). It makes a system with a total of 4 backplanes (2x SAS + 2x SAS2) each of them connected to a 4 different HBA (2x LSI 3081E-R (1068 chip) + 2x LSI

GigE wasn''t giving me the performance I had hoped for so I spring for some 10Gbe cards. So what am I doing wrong. My setup is a Dell 2950 without a raid controller, just a SAS6 card. The setup is as such : mirror rpool (boot) SAS 10K raidz SSD 467 GB on 3 Samsung 256 MLC SSD (220MB/s each) to create the raidz I did a simple zpool create raidz SSD c1xxxxx c1xxxxxx c1xxxxx. I have

I have historically noticed that in ZFS, when ever there is a heavy writer to a pool via NFS, the reads can held back (basically paused). An example is a RAID10 pool of 6 disks, whereby a directory of files including some large 100+MB in size being written can cause other clients over NFS to pause for seconds (5-30 or so). This on B70 bits. I''ve gotten used to this behavior over NFS, but