From 6af905832418cbb68ddebfced3a876c57808132c Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 12 Apr 2019 12:01:41 +0200 Subject: [PATCH] NEWS: document kernel.pid_max change --- NEWS | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/NEWS b/NEWS index f7b145f20e4..4df29b90e98 100644 --- a/NEWS +++ b/NEWS @@ -1,5 +1,26 @@ systemd System and Service Manager +CHANGES WITH 243 in spe: + + * The "kernel.pid_max" sysctl is now bumped to 4194304 by default, + i.e. the full 22bit range the kernel allows, up from the old 16bit + range. This should improve security and robustness a bit, as PID + collisions are made less likely (though certainly still + possible). There are rumours this might create compatibility + problems, though at this moment no practical ones are known to + us. Downstream distributions are hence advised to undo this change in + their builds if they are concerned about maximum compatibility, but + for everybody else we recommend leaving the value bumped. Besides + improving security and robustness this should also simplify things as + the maximum number of allowed concurrent tasks was previously bounded + by both "kernel.pid_max" and "kernel.threads-max" and now only a + single knob is left ("kernel.threads-max"). There have been concerns + that usability is affected by this change because larger PID numbers + are harder to type, but we believe the change from 5 digit PIDs to 7 + digit PIDs is not too hampering for usability. + + … + CHANGES WITH 242: * In .link files, MACAddressPolicy=persistent (the default) is changed -- 2.39.2