From 06cba6ccd165ca8b224797e37fccb9e63f026d77 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 21 Mar 2020 11:28:17 +0100 Subject: Adding upstream version 1.9.1. Signed-off-by: Daniel Baumann --- iredis/data/commands/config-rewrite.md | 37 ++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 iredis/data/commands/config-rewrite.md (limited to 'iredis/data/commands/config-rewrite.md') diff --git a/iredis/data/commands/config-rewrite.md b/iredis/data/commands/config-rewrite.md new file mode 100644 index 0000000..54509e5 --- /dev/null +++ b/iredis/data/commands/config-rewrite.md @@ -0,0 +1,37 @@ +The `CONFIG REWRITE` command rewrites the `redis.conf` file the server was +started with, applying the minimal changes needed to make it reflect the +configuration currently used by the server, which may be different compared to +the original one because of the use of the `CONFIG SET` command. + +The rewrite is performed in a very conservative way: + +- Comments and the overall structure of the original redis.conf are preserved as + much as possible. +- If an option already exists in the old redis.conf file, it will be rewritten + at the same position (line number). +- If an option was not already present, but it is set to its default value, it + is not added by the rewrite process. +- If an option was not already present, but it is set to a non-default value, it + is appended at the end of the file. +- Non used lines are blanked. For instance if you used to have multiple `save` + directives, but the current configuration has fewer or none as you disabled + RDB persistence, all the lines will be blanked. + +CONFIG REWRITE is also able to rewrite the configuration file from scratch if +the original one no longer exists for some reason. However if the server was +started without a configuration file at all, the CONFIG REWRITE will just return +an error. + +## Atomic rewrite process + +In order to make sure the redis.conf file is always consistent, that is, on +errors or crashes you always end with the old file, or the new one, the rewrite +is performed with a single `write(2)` call that has enough content to be at +least as big as the old file. Sometimes additional padding in the form of +comments is added in order to make sure the resulting file is big enough, and +later the file gets truncated to remove the padding at the end. + +@return + +@simple-string-reply: `OK` when the configuration was rewritten properly. +Otherwise an error is returned. -- cgit v1.2.3