Autoraid 12H

[ALH]

Does a lot of small files on an autoraid decrease performce?

[Pedro Sousa]

it depends on which type of RAID you're working with!
RAID 0? Shouldn't be a problem.

[Mark van Silfhout]

I think that the type of filesystem and the used blocksize (ie, vxfs with 1kb blocksize vs. hfs with 8kb blocksize) is a more determining factor than the autoraid, in this case.

[ALH]

The filesystem is VxFS with a blocksize of 1K.
On the filesystem there are 200000 logfiles.

[A. Clay Stephenson]

I have filesystems with > 500000 small files (most less than 2k in size) on multiple application servers and on one system
the physical disks are JBOD's (mirrored) and on another system the same filesystem with essentially identical files resides on a 12H.
Performance levels are comparable and acceptable. The key to maintaining good AutoRAID performance is never exceed about 70% capacity as allocated LUN's to maintain RAID 0/1 space as high as possible. The other performance trick is to comprise each volume group of 2 identically sized LUN'S on the same AutoRAID. The first LUN's primary path should be thru controller X (alternate Y); the second's primary path should be thru controller Y (alt X). Each logical volume should be stripped across both LUN's. This way both external SCSI paths are fully utilized.