3
votes
1answer
71 views

Why would zfs performance be bad for moving files within an fs?

On my FreeNAS NAS (9.1.1 running zfs v28), I am getting terrible performance for file moves between two directories in the same raidz fs. Is this expected? How can I fault-find this, if not? The ...
1
vote
2answers
644 views

High load with low CPU usage and low IO usage on Solaris with ZFS and MySQL

I have a Solaris 10 x86_64 system running MySQL 5.5. Under heavy usage times, we're getting very slow responses from the database: slow queries running into minutes that normally return in sub-second ...
8
votes
1answer
2k views

Is calculating IOPS for ZFS RAIDZ different then calculating IOPS for RAID5 & RAID6?

When calculating IOPS for traditional RAID arrays, one could use the following formula (Borrowed from Getting The Hang Of IOPS v1.3 on Symantec Connect): Ieffective = (n * Isingle) / (READ% + (F * ...
4
votes
1answer
311 views

Why am I getting slow and jumpy ZFS write performance?

I have a 10-disk RAIDZ in Solaris 11.1. Its connected by 8G fibre. I have created a ZVOL, made it available with COMSTAR and mounted it on another machine connected by fibre. When I benchmark it ...
7
votes
2answers
515 views

Does speed of ZFS snapshot rollback depend on number of files?

I have tested a 10Gbit connection between two hosts to be able to read a 10GB file from host1 and write it to host2 using netcat, where the speed was 410MB/s. When I ZFS send/receive again with ...
0
votes
2answers
228 views

How to find files with top io on solaris ZFS?

I have a Solaris 10 ZFS based NFS server. The physical disks are more or less at their maximum io rates. Performance is very bad - so we will add spindles. The NFS solely serves as storage for ...
2
votes
2answers
1k views

Why does doing large deletes, copies, moves on my ZFS NAS block all other IOs?

I've got a Solaris 11 ZFS-based NAS device with 12x1TB 7.2k rpm SATA drives in a mirrored configuration. It provides 2 services from the same pool - an NFS server for a small VM farm and a CIFS ...
0
votes
3answers
1k views

Disk throughput dramatically reduced when using ZFS on OpenSolaris?

I'm building a simple ZFS file server for the small business I work for. The server is a Dell Poweredge 840, with 1GB RAM. The OS (OpenSolaris 2009.06) is installed on one SATA drive, and there are ...
3
votes
1answer
850 views

COMSTAR and ZFS zvol giving bursty write pattern

I've just built a small NAS/SAN box and am doing some testing with it. Configuration is: 2GB RAM 2x Opteron 265s Iwill DK8N 5x500GB SATA drives (1 spare, rest mirrored) = 1TB usable space Emulex ...
3
votes
5answers
979 views

ZFS pool config - advice required

We have 20 2TB SATA drives to be used in a ZFS pool. I am after some advice on the best way to achieve good I/O performance, whilst being able to offer some redundancy (3 disk failures before data ...
4
votes
2answers
2k views

ZFS with L2ARC (SSD) slower for random seeks than without L2ARC

I am currently testing ZFS (Opensolaris 2009.06) in an older fileserver to evaluate its use for our needs. Our current setup is as follows: Dual core (2,4 GHz) with 4 GB RAM 3x SATA controller with ...
8
votes
5answers
4k views

Which is faster for read access on EC2; local drive or EBS?

Which is faster for read access on an EC2 instance; the "local" drive or an attached EBS volume? I have some data that needs to be persisted so have placed this on an EBS volume. I'm using ...
0
votes
3answers
2k views

Monitoring a ZFS Raid Pool on Ubuntu for Integrity and Performance

I set up ZFS on Ubuntu (via fuse) for a storage array at home and it has worked great for almost a year now, despite its 'beta' status. I log in and check the array every once in a while using: zpool ...
1
vote
2answers
1k views

NTFS journal on different (SSD) disk

Some advanced file systems, like ZFS have the option of using SSD disks as a second level cache for the file system or for the journal. Is this possible with NTFS?
0
votes
1answer
653 views

SAS Array with or without expander

Is it better to use a SAS Expander backplane for 12 drives via one SAS connection or is it better to use a SAS backplane with 3 SAS connections? This is in terms of performance, rather than expansion. ...