http://kernelnewbies.org/Linux_2_6_31#head-799157cd8729eba8ee5bc1ff0290d7414f366ef2
fta: --- 1.3. Improve desktop interactivity under memory pressure PROT_EXEC pages are pages that normally belong to some currently running executables and their linked libraries, they shall really be cached aggressively to provide good user experiences because if they aren't, the desktop applications will experience very long and noticeable pauses when the application's code path jumps to a part of the code which is not cached in memory and needs to be read from the disk, which is very slow. Due to some memory management scalability work in recent kernel versions, there're some (commonly used) workloads which can send these PROT_EXEC pages to the list of filesystem-backed pages (the ones used to map files) which are unactive and can get flushed out of the working set. The result is a desktop environment with poor interactivity: the applications become unresponsive too easily. In this version, some heuristics have been used to make much harder to get the mapped executable pages out of the list of active pages. The result is an improved desktop experience: Benchmarks on memory tight desktops show clock time and major faults reduced by 50%, and pswpin numbers are reduced to ~1/3, that means X desktop responsiveness is doubled under high memory/swap pressure. Memory flushing benchmarks in a file server shows the number of major faults going from 50 to 3 during 10% cache hot reads. See the commit link for more details and benchmarks. --- ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _____________________________________________________________________ Ltsp-discuss mailing list. To un-subscribe, or change prefs, goto: https://lists.sourceforge.net/lists/listinfo/ltsp-discuss For additional LTSP help, try #ltsp channel on irc.freenode.net
