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From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Zaphod Beeblebrox <zbeeble@gmail.com>
Subject: Re: iSCSI vs. SMB with ZFS.
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> about the same as the local disk for some operations --- faster for
> some, slower for others.  The workstation has 12G of memory and it's
> my perception that iSCSI is heavily cached and that this enhances it's

any REAL test means doing something that will not fit in cache.

> But this is imperfect.  The iSCSI disk reserves all of it's space and
> the files on the disk are only accessible to the computer that mounts
> it.

it is even more imperfect. you layout one filesystem over another 
filesystem. not only degraded performance but you don't have 
parallel access to files on this "disk".

> The performance on the SMB share is abysmal compared to the
> performance on the iSCSI share.  At the very least, there seems to be
> little benifit to launching the same application twice --- which is
> most likely windows fault.

This is SMB protocol. sorry it is stupid. And it doesn't make real use of 
cache.
This is how windows file sharing works. Fine if you just want to copy 
files. not fine if you work on them.

> Will SMB always have significantly less performance than iSCSI coming
depends what you do but yes SMB is not efficient.

i am happy with SMB as it is enough to store users or shared documents.
And it is quite fast on large file copy etc.

but terrible on randomly accessing files.