From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09F62C43461 for ; Wed, 7 Apr 2021 11:54:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C595E6138B for ; Wed, 7 Apr 2021 11:54:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236215AbhDGLzB (ORCPT ); Wed, 7 Apr 2021 07:55:01 -0400 Received: from mx2.suse.de ([195.135.220.15]:37682 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230280AbhDGLy7 (ORCPT ); Wed, 7 Apr 2021 07:54:59 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1617796489; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=ddpRdKT9wYCe24wptl48nZTWB76xl1PPFUiBI9ZFlHc=; b=QFoOzYFZ0klurN8wSeF86h+RI9rN+UuqSPcBbyy8RJng6XIlHnfWMeTHox7cZfeZt+C5up IdTrJTby1hXTKYzqoM9y5QoZmFJlJcg+lUTdDJxia8mjFwD9liJruBWN6bdZk+jFuCcG3f 0eAeBs4xLCWH7V9RTPR8x4Ev4k5H4Ik= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E116FB12B; Wed, 7 Apr 2021 11:54:48 +0000 (UTC) Date: Wed, 7 Apr 2021 13:54:48 +0200 From: Michal Hocko To: Bharata B Rao Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, aneesh.kumar@linux.ibm.com Subject: Re: High kmalloc-32 slab cache consumption with 10k containers Message-ID: References: <20210405054848.GA1077931@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210405054848.GA1077931@in.ibm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 05-04-21 11:18:48, Bharata B Rao wrote: > Hi, > > When running 10000 (more-or-less-empty-)containers on a bare-metal Power9 > server(160 CPUs, 2 NUMA nodes, 256G memory), it is seen that memory > consumption increases quite a lot (around 172G) when the containers are > running. Most of it comes from slab (149G) and within slab, the majority of > it comes from kmalloc-32 cache (102G) Is this 10k cgroups a testing enviroment or does anybody really use that in production? I would be really curious to hear how that behaves when those containers are not idle. E.g. global memory reclaim iterating over 10k memcgs will likely be very visible. I do remember playing with similar setups few years back and the overhead was very high. -- Michal Hocko SUSE Labs