Re: [zfs-discuss] SSD drives in Sun Fire X4540 or X4500 for dedicated ZIL device
On Thu, 22 Jan 2009, Ross wrote: However, now I've written that, Sun use SATA (SAS?) SSD's in their high end fishworks storage, so I guess it definately works for some use cases. But the fishworks (Fishworks is a development team, not a product) write cache device is not based on FLASH. It is based on DRAM. The difference is like night and day. Apparently there can also be a read cache which is based on FLASH. Bob == Bob Friesenhahn bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer,http://www.GraphicsMagick.org/ ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] SSD drives in Sun Fire X4540 or X4500 for dedicated ZIL device
That's my understanding too. One (STEC?) drive as a write cache, basically a write optimised SSD. And cheaper, larger, read optimised SSD's for the read cache. I thought it was an odd strategy until I read into SSD's a little more and realised you really do have to think about your usage cases with these. SSD's are very definitely not all alike. On Fri, Jan 23, 2009 at 4:33 PM, Greg Mason gma...@msu.edu wrote: If i'm not mistaken (and somebody please correct me if i'm wrong), the Sun 7000 series storage appliances (the Fishworks boxes) use enterprise SSDs, with dram caching. One such product is made by STEC. My understanding is that the Sun appliances use one SSD for the ZIL, and one as a read cache. For the 7210 (which is basically a Sun Fire X4540), that gives you 46 disks and 2 SSDs. -Greg Bob Friesenhahn wrote: On Thu, 22 Jan 2009, Ross wrote: However, now I've written that, Sun use SATA (SAS?) SSD's in their high end fishworks storage, so I guess it definately works for some use cases. But the fishworks (Fishworks is a development team, not a product) write cache device is not based on FLASH. It is based on DRAM. The difference is like night and day. Apparently there can also be a read cache which is based on FLASH. Bob == Bob Friesenhahn bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer,http://www.GraphicsMagick.org/ ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] SSD drives in Sun Fire X4540 or X4500 for dedicated ZIL device
If i'm not mistaken (and somebody please correct me if i'm wrong), the Sun 7000 series storage appliances (the Fishworks boxes) use enterprise SSDs, with dram caching. One such product is made by STEC. My understanding is that the Sun appliances use one SSD for the ZIL, and one as a read cache. For the 7210 (which is basically a Sun Fire X4540), that gives you 46 disks and 2 SSDs. -Greg Bob Friesenhahn wrote: On Thu, 22 Jan 2009, Ross wrote: However, now I've written that, Sun use SATA (SAS?) SSD's in their high end fishworks storage, so I guess it definately works for some use cases. But the fishworks (Fishworks is a development team, not a product) write cache device is not based on FLASH. It is based on DRAM. The difference is like night and day. Apparently there can also be a read cache which is based on FLASH. Bob == Bob Friesenhahn bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer,http://www.GraphicsMagick.org/ ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] SSD drives in Sun Fire X4540 or X4500 for dedicated ZIL device
We're evaluating the possibility of speeding up NFS operations of our X4540s with dedicated log devices. What we are specifically evaluating is replacing 1 or two of our spare sata disks with sata SSDs. Has anybody tried using SSD device(s) as dedicated ZIL devices in a X4540? Are there any known technical issues with using a SSD in a X4540? -Greg ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] SSD drives in Sun Fire X4540 or X4500 for dedicated ZIL device
I don't have an x4540, and this may not be relevant to your usage, but the concern I would have would be how this is going to affect throughput. An x4540 can stream data to and from the disk far faster than any SATA SSD, or even a pair of SATA SSD's can. I'd be nervous about improving my latency at the cost of throughput. I've read that ZFS is supposed to stream large writes directly to disk to avoid this, but I've also read about this not always working (no links I'm afraid, this was a while ago). For an x4540, what I'd be watching are the PCIe SSD devices, and hoping that either Fusion-io or Micron release Solaris drivers for them. -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] SSD drives in Sun Fire X4540 or X4500 for dedicated ZIL device
However, now I've written that, Sun use SATA (SAS?) SSD's in their high end fishworks storage, so I guess it definately works for some use cases. -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
