Feature changed by: Rémy Marquis (Spyhawk) Feature #306397, revision 2 Title: Use VFS cache directly for reads in NSS Requested by: Paul Taysom (taysom) Description: Greg Pachner suggested that we try to satisfy NSS read requests straight from the Linux cache without going into NSS. This means not getting the NSS spinlock to satisfy a read operation. Since almost 40% of the NetBench requests are reads (but not time), this looked like a good bet.   I implemented this approach (it has some hacks and is not of the level of quality to be checked in).   Results: 8 Processor, 32 bit NetBench went from 720 to 836 for the peak, a gain of 15% 2 Processor, 32 bit NetBench went from 559 to 578 for the peak, a gain of 3%   This is a change we want to consider for OES-3. Way too risky for Sp2. NSS does not currently check and update all the page status bits to make this fully work, have to study interactions with zAPIs, and changes the semantics of NSS for pages being modified. You can now read a page while it is being modified. Both the Traditional File System and all Unix file systems have this attribute but it is a change for NSS. + Discussion: + #1: Rémy Marquis (spyhawk) (2009-05-15 17:34:36) + Duplicate of Feature #306398 -- openSUSE Feature: https://features.opensuse.org/306397