>    200-500... impressive for a SAN... but considering the bandwidth
> you have to the box (4x1+10), I'd hope for at least 200 (what I get
> w/just a 10)... so must be some parallel TCP channels there... he..
> What showed those speeds?  I'm _guessing_, but its likely that pvmove
> is single threaded.  So could be related to the I/O transfer size as
> @pattonme was touching on, since multi-threaded I/O can slow things
> down for local I/O when local I/O is in the .5-1GBps and higher range.

Well, it’s a Compellent thing with net storage of around 350TiB, of which 
around 20 is on SSDs, so really, it should be good. Tiering is turned off 
during migration of this data, though (that is, we’re migrating the data 
directly to a low tier, since it’s 40TiB worth of archives).

>    Curious -- do you know your network's cards' MTU size?
> I know that even w/1Gb cards I got 2-4X speed improvement over
> standard 1500 packets (run 9000/9014 byte MTU's over local net).

Everything’s using jumboframes (9000) on the SAN (storage network), and it’s a 
dedicated network with its own switches and copper/fiber. The rest of the 
system works well (at least the Compellent things, EqualLogic has a bad nervous 
breakdown on its way to the cemetery, but that’s another story. The Exchange 
servers running off it, gave us around 400MB/s (that is, wirespeed) last 
backup. That wasn’t raw i/o from vmware, this is, but then again, I should at 
least be able to sustain a gigabit link (the EQL storage is hardly in use 
anymore, perhaps that’s why it’s depressed), and as shown, I’m limited to 
around half of that.

Vennlig hilsen / Best regards

roy
--
Roy Sigurd Karlsbakk
(+47) 98013356
http://blogg.karlsbakk.net/
GPG Public key: http://karlsbakk.net/roysigurdkarlsbakk.pubkey.txt
--
Da mihi sis bubulae frustrum assae, solana tuberosa in modo Gallico fricta, ac 
quassum lactatum coagulatum crassum. Quod me nutrit me destruit.

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