We've been using OpenVZ on many of our servers and the experience has 
been mostly positive. In this case the host system is running CentOS5.

I while ago I noticed odd vzsplit behavior: no matter how many VE's I 
defined, the VMGUARPAGES and PRIVVMPAGES variables were identical. Other 
parameters seem to get scaled up and down as they're supposed to. I 
found nothing useful in mailing list archives (2007) nor in the Wiki.

This memory allocation problem means that we have to calculate the 
amount of memory for each VE by hand  - otherwise the VE's will very 
soon run out of memory. This is rather annoying, because vzsplit is 
otherwise quite convenient tool.

Should I file a bug report on this?

On the left "vzsplit -n 2", on the right "vzsplit -n 4"

# Primary parameters		# Primary parameters
NUMPROC="4000:4000"		NUMPROC="2000:2000"
AVNUMPROC="1117:1117"		AVNUMPROC="558:558"
NUMTCPSOCK="4000:4000"		NUMTCPSOCK="2000:2000"
NUMOTHERSOCK="4000:4000"        NUMOTHERSOCK="2000:2000"
VMGUARPAGES="310952:2147483647" VMGUARPAGES="310952:2147483647"

# Secondary parameters		# Secondary parameters
KMEMSIZE="91539865:100693851"	KMEMSIZE="45769932:50346925"
TCPSNDBUF="14129288:30513288"	TCPSNDBUF="7064644:15256644"
TCPRCVBUF="14129288:30513288"	TCPRCVBUF="7064644:15256644"
OTHERSOCKBUF="7064644:23448644"	OTHERSOCKBUF="3532322:11724322"
DGRAMRCVBUF="7064644:7064644"	DGRAMRCVBUF="3532322:3532322"
OOMGUARPAGES="310952:2147483647" OOMGUARPAGES="310952:2147483647"
PRIVVMPAGES="310952:342047"	PRIVVMPAGES="310952:342047"

# Auxiliary parameters		# Auxiliary parameters
LOCKEDPAGES="4469:4469"		LOCKEDPAGES="2234:2234"
SHMPAGES="31095:31095"		SHMPAGES="31095:31095"
PHYSPAGES="0:2147483647"	PHYSPAGES="0:2147483647"
NUMFILE="35744:35744"		NUMFILE="17856:17856"
NUMFLOCK="1000:1100"		NUMFLOCK="1000:1100"
NUMPTY="400:400"		NUMPTY="200:200"
NUMSIGINFO="1024:1024"		NUMSIGINFO="1024:1024"
DCACHESIZE="19988877:20588544"	DCACHESIZE="9985491:10285056"
NUMIPTENT="200:200"		NUMIPTENT="200:200"
DISKSPACE="1241999:1366199"	DISKSPACE="620999:683099"
DISKINODES="1874472:2061920"	DISKINODES="937236:1030960"
CPUUNITS="113358"		CPUUNITS="68015"