[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [PATCH v3 1/2] tools/xenstore: set oom score for xenstore daemon on Linux
On 30.07.21 15:26, Ian Jackson wrote: Juergen Gross writes ("[PATCH v3 1/2] tools/xenstore: set oom score for xenstore daemon on Linux"):Xenstored is absolutely mandatory for a Xen host and it can't be restarted, so being killed by OOM-killer in case of memory shortage is to be avoided. Set /proc/$pid/oom_score_adj (if available) per default to -500 (this translates to 50% of dom0 memory size) in order to allow xenstored to use large amounts of memory without being killed....+## Type: integer +## Default: 50 +# +# Percentage of dom0 memory size the xenstore daemon can use before the +# OOM killer is allowed to kill it. +#XENSTORED_OOM_MEM_THRESHOLD=50 + ## Type: string ## Default: @LIBEXEC@/boot/xenstore-stubdom.gzThanks for working on this. I approve of the principle. I have one question about detail:} + [ -z "$XENSTORED_OOM_MEM_THRESHOLD" ] || XENSTORED_OOM_MEM_THRESHOLD=50 + XS_OOM_SCORE=-$(($XENSTORED_OOM_MEM_THRESHOLD * 10)) + + rm -f @XEN_RUN_DIR@/xenstored.pid...+ XS_PID=`cat @XEN_RUN_DIR@/xenstored.pid` + echo $XS_OOM_SCORE >/proc/$XS_PID/oom_score_adjThe effect of all this is that the value specified in XENSTORED_OOM_MEM_THRESHOLD is transformed before being echoed into /proc, by being multiplied by -10. Yes. Of course an alternative would be to ask the user to specify the tuneable directly but given its rather more obscure semantics I think it is reasonable to have this done by the script. Correct. Otherwise the user would need to know about the oom_score_adj ABI. But maybe we could add something to the doc comment ? Eg # (The specified value is multiplied by -10 and echoed into # /proc/PID/oom_score_adj.) ? Why? This is an internal implementation detail. I don't see why the user needs to know how this is accomplished. What is unclear with the XENSTORED_OOM_MEM_THRESHOLD semantics as described? There is no other parameter with an explanation how it's semantics are being accomplished. Juergen Attachment:
OpenPGP_0xB0DE9DD628BF132F.asc Attachment:
OpenPGP_signature
|
![]() |
Lists.xenproject.org is hosted with RackSpace, monitoring our |