From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [IPv6:2a01:7e0:0:424::9]) by lore.proxmox.com (Postfix) with ESMTPS id CA7541FF17E for ; Thu, 18 Sep 2025 18:51:24 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 3988A6015; Thu, 18 Sep 2025 18:51:38 +0200 (CEST) To: pve-devel@lists.proxmox.com Date: Thu, 18 Sep 2025 18:45:49 +0200 MIME-Version: 1.0 Message-ID: List-Id: Proxmox VE development discussion List-Post: From: Alwin Antreich via pve-devel Precedence: list Cc: Alwin Antreich X-Mailman-Version: 2.1.29 X-BeenThere: pve-devel@lists.proxmox.com List-Subscribe: , List-Unsubscribe: , List-Archive: Reply-To: Proxmox VE development discussion List-Help: Subject: [pve-devel] [PATCH docs] pveceph: update OSD memory considerations Content-Type: multipart/mixed; boundary="===============5005961625478470657==" Errors-To: pve-devel-bounces@lists.proxmox.com Sender: "pve-devel" --===============5005961625478470657== Content-Type: message/rfc822 Content-Disposition: inline Return-Path: X-Original-To: pve-devel@lists.proxmox.com Delivered-To: pve-devel@lists.proxmox.com Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 355AED24CF for ; Thu, 18 Sep 2025 18:51:36 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 18B9C5F5B for ; Thu, 18 Sep 2025 18:51:36 +0200 (CEST) Received: from mx.antreich.com (mx.antreich.com [173.249.42.230]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Thu, 18 Sep 2025 18:51:34 +0200 (CEST) Received: from mx.antreich.com (localhost [127.0.0.1]) by mx.antreich.com (Proxmox) with ESMTP id E3555764E77 for ; Thu, 18 Sep 2025 18:45:59 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=antreich.com; h= cc:content-transfer-encoding:date:from:from:message-id :mime-version:reply-to:subject:subject:to:to; s=2025; bh=Twc5c1H OO09Ar5VP5szGSHn4JvGNyVSu+pHE6xCUbSk=; b=R9OzI4PIUaGjFuYOtRZyCgS XQCr7C6hMeTiqgGzDqkBjnUXeIJd28FufwXIv2qMNJbEuc9API83Otl999aJ1irF 3juwk9zjDzNxsCMstaFq3JV69hwfBoXfmaVL1odZqwW4ZNuhTo946VMPhVlv+bY9 ZmFu12W91XkjdAkjHwXny8vfp0ZLRE2sq9Ce+mhvZ4KS4FAfFO6rYIENA2Ku4JXL VBvy9/bBURiO56/EE/hQ+Xi4jY1bSmdJUkLdY80BOymX6irahzyFLVtwhUgdF6zj yVgznGWVLNkAX1+N+4HA4F5ucd2e191hUXPplXL/dkOXqR/zTLnZznjUm1neGgA= = From: Alwin Antreich To: pve-devel@lists.proxmox.com Subject: [PATCH docs] pveceph: update OSD memory considerations Date: Thu, 18 Sep 2025 18:45:49 +0200 Message-Id: <20250918164549.3018879-1-alwin@antreich.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.094 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DKIM_SIGNED 0.1 Message has a DKIM or DK signature, not necessarily valid DKIM_VALID -0.1 Message has at least one valid DKIM or DK signature DKIM_VALID_AU -0.1 Message has a valid DKIM or DK signature from author's domain DKIM_VALID_EF -0.1 Message has a valid DKIM or DK signature from envelope-from domain DMARC_PASS -0.1 DMARC pass policy RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_RPBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_SAFE_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. SPF_HELO_PASS -0.001 SPF: HELO matches SPF record SPF_PASS -0.001 SPF: sender matches SPF record Since bluestore, OSDs adhere to the osd_memory_target and the recommended amount of memory was increased. See: https://docs.ceph.com/en/reef/start/hardware-recommendations/#ram Signed-off-by: Alwin Antreich --- pveceph.adoc | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/pveceph.adoc b/pveceph.adoc index 17efa4d..a2d71e7 100644 --- a/pveceph.adoc +++ b/pveceph.adoc @@ -131,14 +131,14 @@ carefully planned out and monitored. In addition to the predicted memory usage of virtual machines and containers, you must also account for having enough memory available for Ceph to provide excellent and stable performance. -As a rule of thumb, for roughly **1 TiB of data, 1 GiB of memory** will be used -by an OSD. While the usage might be less under normal conditions, it will use -most during critical operations like recovery, re-balancing or backfilling. -That means that you should avoid maxing out your available memory already on -normal operation, but rather leave some headroom to cope with outages. - -The OSD service itself will use additional memory. The Ceph BlueStore backend of -the daemon requires by default **3-5 GiB of memory** (adjustable). +While usage may be less under normal conditions, it will consume more memory +during critical operations, such as recovery, rebalancing, or backfilling. That +means you should avoid maxing out your available memory already on regular +operation, but rather leave some headroom to cope with outages. + +The current recommendation is to configure at least **8 GiB of memory per OSD +daemon** for good performance. The OSD daemon requires, by default, 4 GiB of +memory. [[pve_ceph_recommendation_network]] .Network -- 2.39.5 --===============5005961625478470657== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel --===============5005961625478470657==--