Re: [Sks-devel] Clocks, timers, PTree and wiki advice

[Christian Felsing]

Am 24.03.2012 23:26, schrieb Phil Pennock:
>   Virtual Machine issues
> 
>   There are some issues with clock-keeping mechanisms in some virtual
>   machines (VMs) affecting the Berkeley DB used for PTrees; if the clock
>   resolution is too low, multiple entries occur at the same timestamp
>   and the DB becomes corrupted.

After moving to tsc clocksource, ptree problem seems to be void :-) This
may prevent some people for some sleepless nights...

>   kernels locking up on SMP instances. If running SKS in a VM instance,
>   you should probably constrain it to a single CPU.

That is not true for kvm virtualization, my vm guest uses multiple cpus
w/o problems. SKS seems to be stable now.

> Does this make sense to the folks who've encountered and fixed this
> problem?  Is it accurate?

Is this problem really caused by Berkeley DB ? Error message should tell
as much as possible about the cause.

> ...issue.  I also have usually run systems on bare metal, rather than in
> VMs, so this is beyond my expertise.  Folks?

If people do so, I want not to ask them why, because they have
(hopefully) a good reason for doing so. In my case I have a big iron in
a hosting center and this host has to run several different operating
systems.

Christian