some tests use attach_to_replication_stream to watch what's propagated
to replicas, but in some cases the periodic ping may slip in and fail
the test.
we disable that ping by setting the period to once an hour (tests should
not run for that long).
other change is so that the next time this oom-score-adj test fails,
we'll see the value (assert_equals prints it)
The key save delay is too short and on certain systems the child process
is gone before we have a chance to inspect it.
(cherry picked from commit b2a73c404bf277bac287c72494a4c4cd2ba02f8c)
1) cur_test: when restart_server, "no such variable" error occurs
./runtest --single integration/rdb
test {client freed during loading}
SET ::cur_test
restart_server
kill_server
test "Check for memory leaks (pid $pid)"
SET ::cur_test
UNSET ::cur_test
UNSET ::cur_test // This global variable has been unset.
2) `ps --ppid` not available on macOS platform, can be replaced with
`pgrep -P pid`.
(cherry picked from commit f22fa9594d536cb53f83ed8e508c03d4278778b0)
Starting redis 6.0 and the changes we made to the diskless master to be
suitable for TLS, I made the master avoid reaping (wait3) the pid of the
child until we know all replicas are done reading their rdb.
I did that in order to avoid a state where the rdb_child_pid is -1 but
we don't yet want to start another fork (still busy serving that data to
replicas).
It turns out that the solution used so far was problematic in case the
fork child was being killed (e.g. by the kernel OOM killer), in that
case there's a chance that we currently disabled the read event on the
rdb pipe, since we're waiting for a replica to become writable again.
and in that scenario the master would have never realized the child
exited, and the replica will remain hung too.
Note that there's no mechanism to detect a hung replica while it's in
rdb transfer state.
The solution here is to add another pipe which is used by the parent to
tell the child it is safe to exit. this mean that when the child exits,
for whatever reason, it is safe to reap it.
Besides that, i'm re-introducing an adjustment to REPLCONF ACK which was
part of #6271 (Accelerate diskless master connections) but was dropped
when that PR was rebased after the TLS fork/pipe changes (5a47794).
Now that RdbPipeCleanup no longer calls checkChildrenDone, and the ACK
has chance to detect that the child exited, it should be the one to call
it so that we don't have to wait for cron (server.hz) to do that.
Don't assume `ps` handles `-h` to display output without headers and
manually trim headers line from output.
(cherry picked from commit b61b663895f16d9f559a14c408c225062254a57b)
Add Linux kernel OOM killer control option.
This adds the ability to control the Linux OOM killer oom_score_adj
parameter for all Redis processes, depending on the process role (i.e.
master, replica, background child).
A oom-score-adj global boolean flag control this feature. In addition,
specific values can be configured using oom-score-adj-values if
additional tuning is required.
(cherry picked from commit 2530dc0ebd8be8d792f4673073401377cd5bdc42)
Add Linux kernel OOM killer control option.
This adds the ability to control the Linux OOM killer oom_score_adj
parameter for all Redis processes, depending on the process role (i.e.
master, replica, background child).
A oom-score-adj global boolean flag control this feature. In addition,
specific values can be configured using oom-score-adj-values if
additional tuning is required.