Historically, the input and output buffers of a check are allocated by hand
during the startup, with a specific size (not necessarily the same than
other buffers). But since the recent refactoring of the checks to rely
exclusively on the tcp-checks and to use the underlying mux layer, this part
is totally buggy. Indeed, because these buffers are now passed to a mux,
they maybe be swapped if a zero-copy is possible. In fact, for now it is
only possible in h2_rcv_buf(). Thus the bug concretely only exists if a h2
health-check is performed. But, it is a latent bug for other muxes.
Another problem is the size of these buffers. because it may differ for the
other buffer size, it might be source of bugs.
Finally, for configurations with hundreds of thousands of servers, having 2
buffers per check always allocated may be an issue.
To fix the bug, we now allocate these buffers when required using the buffer
pool. Thus not-running checks don't waste memory and muxes may swap them if
possible. The only drawback is the check buffers have now always the same
size than buffers used by the streams. This deprecates indirectly the
"tune.chksize" global option.
In addition, the http-check regtest have been update to perform some h2
health-checks.
Many thanks to @VigneshSP94 for its help on this bug.
This patch should solve the issue #936. It relies on the commit "MINOR:
tcpcheck: Don't handle anymore in-progress send rules in tcpcheck_main".
Both must be backport as far as 2.2.
bla
Its sole remaining purpose was to display "proxy foo started", which
has little benefit and pollutes output for those with plenty of proxies.
Let's remove it now.
The VTCs were updated to reflect this, because many of them had explicit
counts of dropped lines to match this message.
This is tagged as MEDIUM because some users may be surprized by the
loss of this quite old message.
For http-check send rules, it is now possible to use a log-format string to set
the request's body. the keyword "body-lf" should be used instead of "body". If the
string eval fails, no body is added.
For http-check send rules, it is now possible to use a log-format string to set
the request URI. the keyword "uri-lf" should be used instead of "uri". If the
string eval fails, we fall back on the default uri "/".
Christopher Faulet
Willy Tarreau