Re: File system compression, not at the block layer

From: Timothy Miller
Date: Tue Apr 27 2004 - 10:45:09 EST




Ben Greear wrote:
Timothy Miller wrote:

Wouldn't this pretty much guarantee worst-case latency scenario for reading, since
on average at least one of your 32 disks is going to require a full rotation
(and probably a seek) to find it's bit?




Only for the first bit of a block. For large streams of reads, the fifos will keep things going, except for occasionally as drives drift in their relative rotation positions which can cause some delays.


So how is that better than using a striping raid that stripes at the
block level or multi-block level?



It's only better for large streaming writes. The FIFOs I'm talking about above would certainly be smaller than typical RAID0 stripes.

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