From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) by lore.proxmox.com (Postfix) with ESMTPS id E73911FF165 for ; Thu, 14 Aug 2025 13:53:43 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 510F61108A; Thu, 14 Aug 2025 13:55:21 +0200 (CEST) From: Fiona Ebner To: pve-devel@lists.proxmox.com Date: Thu, 14 Aug 2025 13:54:15 +0200 Message-ID: <20250814115443.250599-1-f.ebner@proxmox.com> X-Mailer: git-send-email 2.47.2 MIME-Version: 1.0 X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1755172453343 X-SPAM-LEVEL: Spam detection results: 0 AWL -0.023 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. 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SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: [pve-devel] [PATCH docs] pct: cgroup: update to cgroupv2 being the only supported mode X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Proxmox VE development discussion Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: pve-devel-bounces@lists.proxmox.com Sender: "pve-devel" As already mentioned in the known issues in the roadmap [0], cgroupv2 is the only supported mode in Proxmox VE 9. [0]: https://pve.proxmox.com/wiki/Upgrade_from_8_to_9#cgroup_V1_Removal Signed-off-by: Fiona Ebner --- Didn't want to drop mentioning the differences etc. just yet, because some people were still running in legacy environments. pct.adoc | 39 ++++++++------------------------------- 1 file changed, 8 insertions(+), 31 deletions(-) diff --git a/pct.adoc b/pct.adoc index 529b72f..00d6329 100644 --- a/pct.adoc +++ b/pct.adoc @@ -672,17 +672,15 @@ The main resources controlled via 'cgroups' are CPU time, memory and swap limits, and access to device nodes. 'cgroups' are also used to "freeze" a container before taking snapshots. -There are 2 versions of 'cgroups' currently available, -https://www.kernel.org/doc/html/v5.11/admin-guide/cgroup-v1/index.html[legacy] -and -https://www.kernel.org/doc/html/v5.11/admin-guide/cgroup-v2.html['cgroupv2']. +The current version of 'cgroups' is +https://www.kernel.org/doc/html/v6.14/admin-guide/cgroup-v2.html['cgroupv2']. +There also is a, now unsupported, +https://www.kernel.org/doc/html/v6.14/admin-guide/cgroup-v1/index.html[legacy] +version. -Since {pve} 7.0, the default is a pure 'cgroupv2' environment. Previously a -"hybrid" setup was used, where resource control was mainly done in 'cgroupv1' -with an additional 'cgroupv2' controller which could take over some subsystems -via the 'cgroup_no_v1' kernel command-line parameter. (See the -https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html[kernel -parameter documentation] for details.) +Since {pve} 7.0, the default is a pure 'cgroupv2' environment and since {pve} +9.0, this is the only supported mode. Before {pve} 7.0, a "hybrid" mode was the +default. [[pct_cgroup_compat]] CGroup Version Compatibility @@ -720,29 +718,8 @@ environment, you can either * Move the container, or its services, to a Virtual Machine. Virtual Machines have a much less interaction with the host, that's why one can install decades old OS versions just fine there. - -* Switch back to the legacy 'cgroup' controller. Note that while it can be a - valid solution, it's not a permanent one. Starting from {pve} 9.0, the legacy - controller will not be supported anymore. ==== -[[pct_cgroup_change_version]] -Changing CGroup Version -^^^^^^^^^^^^^^^^^^^^^^^ - -TIP: If file system quotas are not required and all containers support 'cgroupv2', -it is recommended to stick to the new default. - -To switch back to the previous version the following kernel command-line -parameter can be used: - ----- -systemd.unified_cgroup_hierarchy=0 ----- - -See xref:sysboot_edit_kernel_cmdline[this section] on editing the kernel boot -command line on where to add the parameter. - // TODO: seccomp a bit more. // TODO: pve-lxc-syscalld -- 2.47.2 _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel