On Sat, 8 Feb 2014, T L wrote: > How full is the pool? media 16T 6.6T 9.0T 43% /usr/local/media > How much RAM does the system have? 16 GB > Are the ZFS options for de-duplication or compression turned on? I don't remember exactly what I did... forgot how to check, I'll look it up later. > Are you using a L2ARC cache? I don't think so, again have to look up what that is, but preliminary seems like probably not. > If you have any 4k drives, are the filesystem partitions aligned optimally > (ashift=12 maybe)? I actually checked that a few months ago when I was having REALLY horrible performance. Ended up rebuilding the pool in a totally different way and even though my drives should NOT need that parameter, I used it anyway just in case. Performance was fabulous until very recently. There's only one "partition" in the pool. It's two raidz1 pools with four 3tb drives each. > > Thomas > > On Feb 8, 2014 11:09 AM, <tclug at freakzilla.com> wrote: > Hello people, > > Alright, my RAID/ZFS drama continues. The thing was working > perfectly for a few months, and now performance has turned > abysmal. It's a 16TB array running as a media server. If there's > one client streaming data, no problem. Even two. But add a bunch > of little things accessing the pool and it crawls. You hit Play > on a video and there's a 5 second delay before starting. Skip a > music track, again, 5 second delay. Kinda risiculous, right? > > No errors anywhere, zpool srub found nothing wrong, etc. The > server's load average, though, is always super high (like >4, > sometimes up to 6), a lot of waiting for IO. > > The only idea I have is that using the system's built-in SATA to > run eight 3tb harddrives is not able to keep up with demands. So > I'm thinking of getting a nice SATA expeansion card to off-load > some of the processing off the CPU, hopefully that'll help. > > So, a couple questions: > > 1. Can anyone think of any other reason the filesystem is > suddenly acting > like this? It was fine when there was less data on it. > > 2. I feel it should be seemless to move the ZFS pool/drive array > from one > SATA connection to another. I this correct? The array uses > two separate > SATA connections, but I figure worst case I plug them in in > the wrong > order, it fails, I reverse them and restart and no problem. > Is this > true? I don't want to nuke my ZFS pool... > > 3. Can anyone recommend a good SATA card with e-SATA ports? I > have one > that came with the drive enclosure but it is not Linux > compatible. > > > Thanks! > _______________________________________________ > TCLUG Mailing List - Minneapolis/St. Paul, Minnesota > tclug-list at mn-linux.org > http://mailman.mn-linux.org/mailman/listinfo/tclug-list > > >