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 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
