Hello! I've been doing some experiments with OpenVZ, and one of them was, how many VE's can I run on a single machine? The guinea pig machine was a Pentium4/3GHz with 2GB RAM. 230 VE's run just fine, but upon starting the 231st, I reproducably get a kernel panic, "out of memory" (VE configuration is appended below).
What I'd really like to know is, why does that happen? So I collected resource consumption numbers from /proc/bc for all VE's. Summed up for 220 VE's (I didn't dare 230 ;-), the maxheld values are kmemsize 160957978 socket buffers 167838032 (tcpsndbuf+tcprcvbuf+dgramrcvbuf+othersockbuf) physpages 143708 The physpages amount to 562MB; that should fit into 2GB nicely in my book. If I understand <http://wiki.openvz.org/UBC_systemwide_configuration> correctly, those two things need to go into low memory, and the total amount for that on x86 is 832MB. -- Question: Where do the 832 MB come from? The two numbers above are roughly 314 MB, that's nowhere near 832. But the wiki-page has the formula kmemsize+sockbuf / 0.4*832MB should be smaller than 1 to be safe. Interestingly enough, that quotient is 0.94, so there might be something up here. -- Question: Where does the 0.4 come from? Can anybody help me figure out what's going on here? Thank you very much for your help, Wolfgang # VE configuration file NUMFLOCK="100:110" VMGUARPAGES="6144:2147483647" OTHERSOCKBUF="132096:459776" DISTRIBUTION="debian" NUMPTY="16:16" OOMGUARPAGES="6144:2147483647" DGRAMRCVBUF="132096:132096" CPUUNITS="1000" NUMIPTENT="128:128" NUMTCPSOCK="768:768" PHYSPAGES="0:2147483647" AVNUMPROC="50:50" NUMPROC="100:100" LOCKEDPAGES="32:32" TCPSNDBUF="10485760:12451840" VE_ROOT="/var/tmp/vte-wosc/vm33745/root" NUMSIGINFO="256:256" KMEMSIZE="5324800:5857280" SHMPAGES="8192:8192" TCPRCVBUF="10485760:12451840" VE_PRIVATE="/var/tmp/vte-wosc/vm33745/private" NUMFILE="3200:3200" PRIVVMPAGES="32768:36044" DCACHESIZE="1228800:1351680" NUMOTHERSOCK="128:128" OSTEMPLATE="debian-3.1" HOSTNAME="vm0.local" NETIF="ifname=eth0,mac=02:7B:6A:56:00:02,host_ifname=vif33745.0,host_mac=02:7B:6A:56:00:02" _______________________________________________ Users mailing list [email protected] https://openvz.org/mailman/listinfo/users
