Balbir Singh wrote: [snip]
>> And what about a hard limit - how would you fail in page fault in >> case of limit hit? SIGKILL/SEGV is not an option - in this case we >> should run synchronous reclamation. This is done in beancounter >> patches v6 we've sent recently. >> > > I thought about running synchronous reclamation, but then did not follow > that approach, I was not sure if calling the reclaim routines from the > page fault context is a good thing to do. It's worth trying out, since Each page fault potentially calls reclamation by allocating required page with __GFP_IO | __GFP_FS bits set. Synchronous reclamation in page fault is really normal. [snip] >> Please correct me if I'm wrong, but does this reclamation work like >> "run over all the zones' lists searching for page whose controller >> is sc->container" ? >> > > Yeah, that's correct. The code can also reclaim memory from all over-the-limit OK. What if I have a container with 100 pages limit in a 4Gb (~ million of pages) machine and this group starts reclaiming its pages. In case this group uses its pages heavily they will be at the beginning of an LRU list and reclamation code would have to scan through all (million) pages before it finds proper ones. This is not optimal! > containers (by passing SC_OVERLIMIT_ALL). The idea behind using such a scheme > is to ensure that the global LRU list is not broken. isolate_lru_pages() helps in this. As far as I remember this was introduced to reduce lru lock contention and keep lru lists integrity. In beancounters patches this is used to shrink BC's pages. ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ ckrm-tech mailing list https://lists.sourceforge.net/lists/listinfo/ckrm-tech
