[Lustre-discuss] Read-ahead with blockdev --setra ?

Wed May 11 03:59:28 PDT 2011

One of our users has suggested attempting to tune our test Lustre 1.8.5 OSTs by setting a read-ahead parameter on the underlying device via "blockdev --setra". I tried setting this parameter to 8MB for an OST but as soon as the OST was mounted, the parameter reverted back to 640KB. I see absolutely no mention of this method in the Lustre manual. Can someone on the development team please comment on whether this parameter is effective and can actually be tuned?

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Yemi