From 538390d924a591a630b7b451da2fcd6c28dc21d2 Mon Sep 17 00:00:00 2001 From: MichaIng Date: Mon, 14 Oct 2024 16:35:31 +0200 Subject: [PATCH] enh(admin_manual): update OPcache JIT docs Single Nextcloud instances have shown to use less than 2 MiB of the configured JIT buffer size, so that 8 MiB is sufficient by a large margin. Using any larger value pre-occupies the `opcache.memory_consumption` accurdingly and 128 MiB would hence fill its default 128 MiB completely, without any benefit. The example JIT size is hence reduced to 8 MiB. Enabling JIT however has shown to raise overall OPcache usage by a larger amount than the configured JIT size, so that `opcache.memory_consumption` might still need to be raised in some cases. This information is added to the documentation: https://github.com/nextcloud/all-in-one/issues/2755#issuecomment-1591848523 Additionally, the info is added that JIT is currently supported on x86 platforms only. Signed-off-by: MichaIng --- admin_manual/installation/server_tuning.rst | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/admin_manual/installation/server_tuning.rst b/admin_manual/installation/server_tuning.rst index cc8d2ecf182..969e6ad4b7f 100644 --- a/admin_manual/installation/server_tuning.rst +++ b/admin_manual/installation/server_tuning.rst @@ -146,7 +146,7 @@ However, the revalidation frequency can be adjusted and may *potentially* enhanc .. danger:: Lengthening the time between revalidation (or disabling it completely) means that manual changes to scripts, including ``config.php``, will take longer before they become active (or will never do so, if - revalidation is disabled completely). Lengthening also increases the likelihood of transient Server and application upgrade problems. It also prevents the proper toggling of maintenance mode. + revalidation is disabled completely). Lengthening also increases the likelihood of transient server and application upgrade problems. It also prevents the proper toggling of maintenance mode. .. warning:: If you adjust these parameters, you are more likely to need to restart/reload your web server (mod_php) or fpm after making configuration changes or performing upgrades. If you forget to do so, you @@ -189,12 +189,17 @@ Nextcloud strictly requires code comments to be preserved in opcode, which is th JIT ^^^ -PHP 8.0 and above ship with a JIT compiler that can be enabled to benefit any CPU intensive apps you might be running. To enable a tracing JIT with all optimizations: +PHP 8.0 and above ship with a JIT compiler that can be enabled on x86 platforms to benefit any CPU intensive apps you might be running. To enable a tracing JIT with all optimizations: .. code:: ini opcache.jit = 1255 - opcache.jit_buffer_size = 128M + opcache.jit_buffer_size = 8M + +.. note:: + + Single Nextcloud instances have shown to use less than 2 MiB of the configured JIT buffer size, so that 8 MiB is sufficient by a large margin. The overall OPcache usage however raises by a larger amount, so that ``opcache.memory_consumption`` might need to be raised in some cases. The Nextcloud admin panel will then show a related warning. + JIT buffer usage can be monitored with `opcache-gui `_ as well. Previews --------