My understanding is that it won't have much impact. In case of random reads, read cache won't help much (typically low read cache hit ratio). So, changing cache parameters may not help much.  We may need to look at the drives. Maybe have more spindles serving the requests as all (or most) IO requests will be served by disks and not the cache. You may want to check with your local performance specialists before taking a decision on this.  By any chance, is it an iSCSI implementation?  VMware and Windows may gain some performance by changing the delayed ACK feature.  Further read at: [URL]  [URL]  There are different entries for Win 2008 and 2008R2.  These values though are only for iSCSI and have no impact on FC connectivity.  Further details on IO profile and distribution on load along with your actual performance expectation will definitely get you more helpful responses regarding this.  -rupak
Under what scenarios should I look at changing the default page size when troubleshooting performance problems relating to random reads?
When does changing Cache Page Size Help