hello experts, I want’ to change zfs_arc_max value in smartos without reboot the machine, may I know what’s the command used to do that, and how to verify it is changed successed ?

thanks

and also, would like to ask a question, regarding to sys usage is too high when there is more than 10 process running, here is the screen dump by vmstat; pastebin.com/hewQ4WPK, how to avoid it the high sys usage? how to do more investigative in this case? thanks in advance

tozhu: I would do some kernel stack profiling during that window to see what the kernel is doing

e.g., see github.com/brendangregg/FlameGraph#dtrace

jclulow: Thanks for the advice, btw, may I ask how to change ‘zfs_arc_max’ by mdb command without reboot the OS? I read some docs say: echo ‘::zfs_arc_max/W0xxxxx’ | mdb -kw ; but I don’t know /W0xxxx means, where is the docs for the details ?

thank you

I do not believe you can change that value at runtime

Or, more accurately, you can probably change it, but it won't do anything

I'm pretty sure `zfs_arc_max` is used once at boot in `arc_init()`

You will need to change it in `/etc/system`

jclulow: two question for advice: 1.) my server configuration: CPU: 2 socket/packages, 16c/32t per socket, 32c/64t in total; memory is 384G; storage: 24x1.2T at mirror ; this is my server configuration, my question is, how to allowcate vCPU and Memory for a VM, do you have any advice? I use 1vCPU manage 4G mem, usually, a VM had 4vCPU and 16G mem ; 2.) how many memory is adviced for zfs_arc_max

than you;

btw, ‘/etc/system’ is read only for smartos, is there any entry to change it for perim usage?

may I ask what’s the new entry for this old one? rsync://pkgsrc.smartos.org/pkgsrc-joyent do you know? thanks again

sorry, the old name is pkgsrc.joyent.com , may I know what’s the new entry to do rsync, thank you

tozhu: Ideally you would not have to tune zfs_arc_max

Are you experiencing an issue that makes you feel like you need to tune it?

yes, the situation is that: I’m stress a postgresql database, the database is used about 48G memory, and the zfs_arc_max used 280G memory by arcstat command, I don’t know why zfs_arc_max eat so much memory

It will tend to grow to use unused memory

If the database asks for more memory it should begin to shrink

okay, got it, thank you very for the advice

If it doesn't shrink though, we should investigate why not

jclulow, thank you very much

You're welcome!

tozhu: it's now just rsync://pkgsrc.smartos.org/pkgsrc - note that if you only provide a URL to rsync you can use it like a file browser, e.g. running "rsync rsync://pkgsrc.smartos.org" will show you the list of available repositories, and then "rsync rsync://pkgsrc.smartos.org/pkgsrc" will list that repo

jperkin: thank you, does this works for the old version of smartos images/zones ?

could you clarify what you mean?

jperkin: I mean if this site is the full mirror for pkgsrc.joyent.com ?

mostly, yes, if there are old releases that are no longer available then you'll need to grab them from the archive (using manta-sync) at us-central.manta.mnx.io/pkgsrc/public/packages

Hi, how can I forced delete a zone? CloudAPI failed, VMAPI failed and even `vmadm delete` is hanging...

Is it running?

Can I destroy the ZFS datasets and remove the /etc/zones/<uuid>.xml file?

It is running but it has no NICs. It looks like it was never properly created

There are some old jobs that say the zone was successfully destroyed but it still exists and is running with no NICs

Use vmadm stop -F first

Once it's stopped, there shouldn't be any problem deleting it.

I get "cannot manage a zone which is in state 'configured'" when I run `vmadm stop -F` but `vmadm list` shows it's in the "running" state

Should I manually change the state in /etc/zones/<uuid>.xml?

Actually, I don't see any state/status/transition in the zone XML file

`zoneadm -z <vm_uuid> halt` worked followed by `vmadm delete <vm_uuid>`