Make sure you pick instances with PCID cpu capability, their TLB overhead flush overhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas < thomas.steinmau...@dynatrace.com> wrote: > Quick follow up. > > > > Others in AWS reporting/seeing something similar, e.g.: > https://twitter.com/BenBromhead/status/950245250504601600 > > > > So, while we have seen an relative CPU increase of ~ 50% since Jan 4, > 2018, we now also have applied a kernel update at OS/VM level on a single > node (loadtest and not production though), thus more or less double patched > now. Additional CPU impact by OS/VM level kernel patching is more or less > negligible, > so looks highly Hypervisor related. > > > > Regards, > > Thomas > > > > *From:* Steinmaurer, Thomas [mailto:thomas.steinmau...@dynatrace.com] > *Sent:* Freitag, 05. Jänner 2018 12:09 > *To:* user@cassandra.apache.org > *Subject:* Meltdown/Spectre Linux patch - Performance impact on Cassandra? > > > > Hello, > > > > has anybody already some experience/results if a patched Linux kernel > regarding Meltdown/Spectre is affecting performance of Cassandra negatively? > > > > In production, all nodes running in AWS with m4.xlarge, we see up to a 50% > relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, > most likely correlating with Amazon finished patching the underlying > Hypervisor infrastructure … > > > > Anybody else seeing a similar CPU increase? > > > > Thanks, > > Thomas > > > > The contents of this e-mail are intended for the named addressee only. It > contains information that may be confidential. Unless you are the named > addressee or an authorized designee, you may not copy or use it, or > disclose it to anyone else. If you received it in error please notify us > immediately and then destroy it. Dynatrace Austria GmbH (registration > number FN 91482h) is a company registered in Linz whose registered office > is at 4040 Linz, Austria, Freistädterstraße 313 > <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g> > The contents of this e-mail are intended for the named addressee only. It > contains information that may be confidential. Unless you are the named > addressee or an authorized designee, you may not copy or use it, or > disclose it to anyone else. If you received it in error please notify us > immediately and then destroy it. Dynatrace Austria GmbH (registration > number FN 91482h) is a company registered in Linz whose registered office > is at 4040 Linz, Austria, Freistädterstraße 313 > <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g> >
