Hi,
On 10/01/2018 08:46, David Crooks wrote:
> Hi,
>
> I think a particularly interesting comparison would be workloads with significant IO load if anyone has those numbers to compare as well.
yes, the wildest claims about loss of performance are on IO. There
aren't yet systematic tests only people running one off tests jobs
though. What is clear is that HS06 is unaffected.
cheers
alessandra
> Cheers,
> David
>
> On 10/01/2018, 06:30, "Testbed Support for GridPP member institutes on behalf of RAUL H C LOPES" <[log in to unmask] on behalf of [log in to unmask]> wrote:
>
> Hi,
>
> Summary from a linux kernel minder
>
>
> http://kroah.com/log/blog/2018/01/06/meltdown-status/
>
>
> I've tested on several services.
>
> - ArcCE: impact on performance is negligible.
> - 2 old disk servers: same as ArcCE.
>
> I have done it on worker nodes with different CPUs without problems, but
> I don't have performance comparisons. I've seen numbers from CERN
> talking about 1% to 4%.
> I should collect data.
>
> Thanks, raul
>
> On 10/01/18 00:22, Alastair Dewhurst wrote:
> > Hi All
> >
> > Jeremy mentioned in his email regarding OPs meetings that:
> > "There seems to be sufficient discussion on other lists to address the security topic that arose over the holiday period”
> > I assume this was a reference to Spectre and Meltdown. I am on quite a few mail lists but I haven’t seen that much useful discussions.
> >
> > What I have seen:
> > - Emails where people repeatedly forward the OSG and EGI recommendations around slowly obscuring the contents of the message with headers and indentation.
> > - Emails where people argue over what the OSG and EGI recommendations actually mean.
> > - Emails where people ask/confirm if mitigation is available for certain machine types (Which to be fair is perfectly reasonable and useful).
> > - Emails where people have patched a test machine ran a quick benchmark and then made a wild extrapolation… (sometimes the first person just reports the result and lets someone else decide to take it as scientific fact and make the wild extrapolation).
> >
> > What I haven’t seen are any emails where people have said they have patched certain services and after a day or two its fine and all the fears about performance hits did not materialise.
> >
> > At RAL we currently have 50% of the batch farm in draining which will be patched + rebooted around Lunchtime Wednesday, the other half will be done on Thursday. There is a bit of a flu epidemic going around RAL at the moment, so we haven’t started patching other service yet, but we intend to start on Wednesday.
> >
> > Anyone done an ARC CE (+ HTCondor Schedd)? They aren’t massively loaded but they are constantly busy machines and could potentially be impacted by performance slow downs. Our intention is to do one on Wednesday and see if anything happens before doing the rest over the next few days.
> >
> > What about other services run by many sites? Squids, MyProxy, Bdii, PerfSonar, Argus etc? Most of these aren’t heavily used so I don’t expect problems, but its always nice to know if other people have done it. Performance hits on squids could potentially cause a problem if they are loaded, but I guess we could just add another machine or two.
> >
> > Thanks
> >
> > Alastair
> >
>
>
--
Respect is a rational process. \\//
Fatti non foste a viver come bruti, ma per seguir virtute e canoscenza(Dante)
For Ur-Fascism, disagreement is treason. (U. Eco)
But but but her emails... covfefe!
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