On Thu, 2010-04-01 at 11:32 +0200, Eugen Leitl wrote: > Due to space limitations within the 5015A-PHF rackmounts and my > budget limitations I'm thinking about using an 80 GByte Intel > SSD along with a conventional 1-2 TByte SATA drive in a sensible > way for vserver production systems. > > Linux doesn't have any native/production filesystems like zfs yet. > Presumably btrfs will be up to snuff sometime, but it is probably > years away from production still. Yes - waiting eagerly for btrfs > > Presumably one could mount such a hybrid zfs an iSCSI device, but > that would waste the iSCSI host. Also, the GBit Ethernet would > be a bottleneck (at max 115 MByte/s throughput), so one would > have to use channel bonding and an additional network card. We spent a lot of time optimizing a VServer iSCSI environment with a lot of disappointment. Linux (at least on AMD64) is limited to a 4KB block size which makes the iSCSI channel bound by latency rather than throughput. Bonding was also a serious disappointment in a VServer environment. Because we have lots of servers on a single MAC address, most bonding schemes fail because they map traffic flows to MAC SA/DA combinations. Even when using schemes which can look at a higher layer, the attaching switches will likely not support it and collapse it back to MAC SA/DA pairs. Bonding is great in many-to-many but almost useless in few-to-few except for failover. We found ourselves using either software RAID0 across the iSCSI disks (protected on the backend with ZFS) or multi-path in multi-bus mode. > > So I'm thinking about how to use such a hybrid SSD/HD setup manually. > The obvious solutions would be to use the SSD for swap and for /tmp, > and HD for everything else. > > Another idea is to get the whole (vhashified) servers to live > there, and mount /home from the conventional hard disk. > > Any additional ideas? >