Commit Graph

12418 Commits

Author SHA1 Message Date
William Lallemand
d742b6caf7 DOC: fix tune.ssl.keylog sample fetches array
The labels EXPORTER_SECRET and EARLY_EXPORTER_SECRET were swapped in the
array.
2020-07-07 10:25:15 +02:00
William Lallemand
7d42ef5b22 WIP/MINOR: ssl: add sample fetches for keylog in frontend
OpenSSL 1.1.1 provides a callback registering function
SSL_CTX_set_keylog_callback, which allows one to receive a string
containing the keys to deciphers TLSv1.3.

Unfortunately it is not possible to store this data in binary form and
we can only get this information using the callback. Which means that we
need to store it until the connection is closed.

This patches add 2 pools, the first one, pool_head_ssl_keylog is used to
store a struct ssl_keylog which will be inserted as a ex_data in a SSL *.
The second one is pool_head_ssl_keylog_str which will be used to store
the hexadecimal strings.

To enable the capture of the keys, you need to set "tune.ssl.keylog on"
in your configuration.

The following fetches were implemented:

ssl_fc_client_early_traffic_secret,
ssl_fc_client_handshake_traffic_secret,
ssl_fc_server_handshake_traffic_secret,
ssl_fc_client_traffic_secret_0,
ssl_fc_server_traffic_secret_0,
ssl_fc_exporter_secret,
ssl_fc_early_exporter_secret
2020-07-06 19:08:03 +02:00
Ilya Shipitsin
46a030cdda CLEANUP: assorted typo fixes in the code and comments
This is 11th iteration of typo fixes
2020-07-06 14:34:32 +02:00
Willy Tarreau
f278eec37a BUILD: tree-wide: cast arguments to tolower/toupper to unsigned char
NetBSD apparently uses macros for tolower/toupper and complains about
the use of char for array subscripts. Let's properly cast all of them
to unsigned char where they are used.

This is needed to fix issue #729.
2020-07-05 21:50:02 +02:00
Willy Tarreau
b0be8ae2a8 CLEANUP: auth: fix useless self-include of auth-t.h
Since recent include cleanups auth-t.h ended up including itself.
2020-07-05 21:32:47 +02:00
Willy Tarreau
0c439d8956 BUILD: tools: make resolve_sym_name() return a const
Originally it was made to return a void* because some comparisons in the
code where it was used required a lot of casts. But now we don't need
that anymore. And having it non-const breaks the build on NetBSD 9 as
reported in issue #728.

So let's switch to const and adjust debug.c to accomodate this.
2020-07-05 20:26:04 +02:00
Willy Tarreau
4c442b08b3 CLEANUP: makefile: update the outdated list of DEBUG_xxx options
A few options didn't exist anymore (FSM, HASH) and quite a few ones were
added since last update (MEM_STATS, DONT_SHARE_POOLS, NO_LOCKLESS_POOLS,
NO_LOCAL_POOLS, FAIL_ALLOC, STRICT_NOCRASH, HPACK.
2020-07-04 12:43:46 +02:00
Willy Tarreau
46ac781779 BUILD: mux-h2: fix typo breaking build when using DEBUG_LOCK
A typo was accidently introduced in commit 48ce6a3 ("BUG/MEDIUM: muxes:
Make sure nobody stole the connection before using it."), a "&" was
placed in front of "OTHER_LOCK", which breaks DEBUG_LOCK. No backport
is needed.
2020-07-04 07:16:18 +02:00
Willy Tarreau
62f11a589f [RELEASE] Released version 2.2-dev12
Released version 2.2-dev12 with the following main changes :
    - BUG/MINOR: mux_h2: don't lose the leaving trace in h2_io_cb()
    - MINOR: cli: make "show sess" stop at the last known session
    - CLEANUP: buffers: remove unused buffer_wq_lock lock
    - BUG/MEDIUM: buffers: always allocate from the local cache first
    - MINOR: connection: align toremove_{lock,connections} and cleanup into idle_conns
    - CONTRIB: debug: add missing flags SI_FL_L7_RETRY & SI_FL_D_L7_RETRY
    - BUG/MEDIUM: connections: Don't increase curr_used_conns for shared connections.
    - BUG/MEDIUM: checks: Increment the server's curr_used_conns
    - REORG: buffer: rename buffer.c to dynbuf.c
    - REORG: includes: create tinfo.h for the thread_info struct
    - CLEANUP: pool: only include the type files from types
    - MINOR: pools: move the LRU cache heads to thread_info
    - BUG/MINOR: debug: fix "show fd" null-deref when built with DEBUG_FD
    - MINOR: stats: add 3 new output values for the per-server idle conn state
    - MINOR: activity: add per-thread statistics on FD takeover
    - BUG/MINOR: server: start cleaning idle connections from various points
    - MEDIUM: server: improve estimate of the need for idle connections
    - MINOR: stats: add the estimated need of concurrent connections per server
    - BUG/MINOR: threads: Don't forget to init each thread toremove_lock.
    - BUG/MEDIUM: lists: Lock the element while we check if it is in a list.
    - Revert "BUG/MEDIUM: lists: Lock the element while we check if it is in a list."
    - BUG/MINOR: haproxy: don't wake already stopping threads on exit
    - BUG/MINOR: server: always count one idle slot for current thread
    - MEDIUM: server: use the two thresholds for the connection release algorithm
    - BUG/MINOR: http-rules: Fix ACLs parsing for http deny rules
    - BUG/MINOR: sched: properly cover for a rare MT_LIST_ADDQ() race
    - MINOR: mux-h1: avoid taking the toremove_lock in on dying tasks
    - MINOR: mux-h2: avoid taking the toremove_lock in on dying tasks
    - MINOR: mux-fcgi: avoid taking the toremove_lock in on dying tasks
    - MINOR: pools: increase MAX_BASE_POOLS to 64
    - DOC: ssl: add "allow-0rtt" and "ciphersuites" in crt-list
    - BUG/MEDIUM: pattern: Add a trailing \0 to match strings only if possible
    - BUG/MEDIUM: log-format: fix possible endless loop in parse_logformat_string()
    - BUG/MINOR: proxy: fix dump_server_state()'s misuse of the trash
    - BUG/MINOR: proxy: always initialize the trash in show servers state
    - MINOR: cli/proxy: add a new "show servers conn" command
    - MINOR: server: skip servers with no idle conns earlier
    - BUG/MINOR: server: fix the connection release logic regarding nearly full conditions
    - MEDIUM: server: add a new pool-low-conn server setting
    - BUG/MEDIUM: backend: always search in the safe list after failing on the idle one
    - MINOR: backend: don't always takeover from the same threads
    - MINOR: sched: make sched->task_list_size atomic
    - MEDIUM: sched: create a new TASK_KILLED task flag
    - MEDIUM: sched: implement task_kill() to kill a task
    - MEDIUM: mux-h1: use task_kill() during h1_takeover() instead of task_wakeup()
    - MEDIUM: mux-h2: use task_kill() during h2_takeover() instead of task_wakeup()
    - MEDIUM: mux-fcgi: use task_kill() during fcgi_takeover() instead of task_wakeup()
    - MINOR: list: Add MT_LIST_DEL_SAFE_NOINIT() and MT_LIST_ADDQ_NOCHECK()
    - CLEANUP: connections: rename the toremove_lock to takeover_lock
    - MEDIUM: connections: Don't use a lock when moving connections to remove.
    - DOC: configuration: add missing index entries for tune.pool-{low,high}-fd-ratio
    - DOC: configuration: fix alphabetical ordering for tune.pool-{high,low}-fd-ratio
    - MINOR: config: add a new tune.idle-pool.shared global setting.
    - MINOR: 51d: silence a warning about null pointer dereference
    - MINOR: debug: add a new "debug dev memstats" command
    - MINOR: log-format: allow to preserve spacing in log format strings
    - BUILD: debug: avoid build warnings with DEBUG_MEM_STATS
    - BUG/MAJOR: sched: make sure task_kill() always queues the task
    - BUG/MEDIUM: muxes: Make sure nobody stole the connection before using it.
    - BUG/MEDIUM: cli/proxy: don't try to dump idle connection state if there's none
    - BUILD: haproxy: fix build error when RLIMIT_AS is not set
    - BUG/MAJOR: sched: make it work also when not building with DEBUG_STRICT
    - MINOR: log: add time second fraction field to rfc5424 log timestamp.
    - BUG/MINOR: log: missing timezone on iso dates.
    - BUG/MEDIUM: server: don't kill all idle conns when there are not enough
    - MINOR: sched: split tasklet_wakeup() into tasklet_wakeup_on()
    - BUG/MEDIUM: connections: Set the tid for the old tasklet on takeover.
    - BUG/MEDIUM: connections: Let the xprt layer know a takeover happened.
    - BUG/MINOR: http_act: don't check capture id in backend (2)
    - BUILD: makefile: disable threads by default on OpenBSD
    - BUILD: peers: fix build warning with gcc 4.2.1
    - CI: cirrus-ci: exclude slow reg-tests
2020-07-04 07:10:24 +02:00
Ilya Shipitsin
95d8af76c8 CI: cirrus-ci: exclude slow reg-tests
slow tests are racy, we already skip them on travis-ci, let us do the
same in cirrus-ci
2020-07-04 06:58:14 +02:00
Willy Tarreau
a898f0c6ff BUILD: peers: fix build warning with gcc 4.2.1
Building on OpenBSD 6.7 with gcc-4.2.1 yields the following warnings
which suggest that the initialization is not taken as expected but
that the container member is reset with each initialization:

  src/peers.c: In function 'peer_send_updatemsg':
  src/peers.c:1000: warning: initialized field overwritten
  src/peers.c:1000: warning: (near initialization for 'p.updt')
  src/peers.c:1001: warning: initialized field overwritten
  src/peers.c:1001: warning: (near initialization for 'p.updt')
  src/peers.c:1002: warning: initialized field overwritten
  src/peers.c:1002: warning: (near initialization for 'p.updt')
  src/peers.c:1003: warning: initialized field overwritten
  src/peers.c:1003: warning: (near initialization for 'p.updt')
  src/peers.c:1004: warning: initialized field overwritten
  src/peers.c:1004: warning: (near initialization for 'p.updt')

Fixing this is trivial, we just have to initialize one level at
a time.
2020-07-03 19:09:29 +02:00
Willy Tarreau
45e83e8c56 BUILD: makefile: disable threads by default on OpenBSD
As reported by Ilya in issue #725, building with threads on OpenBSD
is broken with gcc:

  include/haproxy/tinfo.h:30: error: thread-local storage not supported for this target

Better stay safe and disable it. Clang seems to support (or emulate)
thread-local, at least it builds. Those willing to experiment can
easily pass USE_THREAD=1.
2020-07-03 18:56:33 +02:00
Tim Duesterhus
f3f4aa0266 BUG/MINOR: http_act: don't check capture id in backend (2)
Please refer to commit 19a69b3740 for all the
details. This follow up commit fixes the `http-response capture` case, the
previous one only fixed the `http-request capture` one. The documentation was
already updated and the change to `check_http_res_capture` is identical to
the `check_http_req_capture` change.

This patch must be backported together with 19a69b3740.
Most likely this is 1.6+.
2020-07-03 18:30:54 +02:00
Olivier Houchard
a74bb7e26e BUG/MEDIUM: connections: Let the xprt layer know a takeover happened.
When we takeover a connection, let the xprt layer know. If it has its own
tasklet, and it is already scheduled, then it has to be destroyed, otherwise
it may run the new mux tasklet on the old thread.

Note that we only do this for the ssl xprt for now, because the only other
one that might wake the mux up is the handshake one, which is supposed to
disappear before idle connections exist.

No backport is needed, this is for 2.2.
2020-07-03 17:49:33 +02:00
Olivier Houchard
1662cdb0c6 BUG/MEDIUM: connections: Set the tid for the old tasklet on takeover.
In the various takeover() methods, make sure we schedule the old tasklet
on the old thread, as we don't want it to run on our own thread! This
was causing a very rare crash when building with DEBUG_STRICT, seeing
that either an FD's thread mask didn't match the thread ID in h1_io_cb(),
or that stream_int_notify() would try to queue a task with the wrong
tid_bit.

In order to reproduce this, it is necessary to maintain many connections
(typically 30k) at a high request rate flowing over H1+SSL between two
proxies, the second of which would randomly reject ~1% of the incoming
connection and randomly killing some idle ones using a very short client
timeout. The request rate must be adjusted so that the CPUs are nearly
saturated, but never reach 100%. It's easier to reproduce this by skipping
local connections and always picking from other threads. The issue
should happen in less than 20s otherwise it's necessary to restart to
reset the idle connections lists.

No backport is needed, takeover() is 2.2 only.
2020-07-03 17:49:23 +02:00
Willy Tarreau
43079e0731 MINOR: sched: split tasklet_wakeup() into tasklet_wakeup_on()
tasklet_wakeup() only checks tl->tid to know whether the task is
programmed to run on the current thread or on a specific thread. We'll
have to ease this selection in a subsequent patch, preferably without
modifying tl->tid, so let's have a new tasklet_wakeup_on() function
to specify the thread number to run on. That the logic has not changed
at all.
2020-07-03 17:19:47 +02:00
Willy Tarreau
18ed789ae2 BUG/MEDIUM: server: don't kill all idle conns when there are not enough
In srv_cleanup_idle_connections(), we compute how many idle connections
are in excess compared to the average need. But we may actually be missing
some, for example if a certain number were recently closed and the average
of used connections didn't change much since previous period. In this
case exceed_conn can become negative. There was no special case for this
in the code, and calculating the per-thread share of connections to kill
based on this value resulted in special value -1 to be passed to
srv_migrate_conns_to_remove(), which for this function means "kill all of
them", as used in srv_cleanup_connections() for example.

This causes large variations of idle connections counts on servers and
CPU spikes at the moment the cleanup task passes. These were quite more
visible with SSL as it costs CPU to close and re-establish these
connections, and it also takes time, reducing the reuse ratio, hence
increasing the amount of connections during reconnection.

In this patch we simply skip the killing loop when this condition is met.

No backport is needed, this is purely 2.2.
2020-07-02 19:05:30 +02:00
Emeric Brun
b39a3754d9 BUG/MINOR: log: missing timezone on iso dates.
The function timeofday_as_iso_us adds now the trailing local timezone offset.
Doing this the function could be use directly to generate rfc5424 logs.

It affects content of a ring if the ring's format is set to 'iso' and 'timed'.
Note: the default ring 'buf0' is of type 'timed'.

It is preferable NOT to backport this to stable releases unless bugs are
reported, because while the previous format is not correct and the new
one is correct, there is a small risk to cause inconsistencies in log
format to some users who would not expect such a change in a stable
cycle.
2020-07-02 17:56:11 +02:00
Emeric Brun
9f9b22c4f1 MINOR: log: add time second fraction field to rfc5424 log timestamp.
This patch adds the time second fraction in microseconds
as supported by the rfc.
2020-07-02 17:56:06 +02:00
Willy Tarreau
4f58926352 BUG/MAJOR: sched: make it work also when not building with DEBUG_STRICT
Sadly, the fix from commit 54d31170a ("BUG/MAJOR: sched: make sure
task_kill() always queues the task") broke the builds without DEBUG_STRICT
as, in order to be careful, it plcaed a BUG_ON() around the previously
failing condition to check for any new possible failure, but this BUG_ON
strips the condition when DEBUG_STRICT is not set. We don't want BUG_ON
to evaluate any condition either as some debugging code calls possibly
expensive ones (e.g. in htx_get_stline). Let's just drop the useless
BUG_ON().

No backport is needed, this is 2.2-dev.
2020-07-02 17:17:42 +02:00
Willy Tarreau
ab8b6a45be BUILD: haproxy: fix build error when RLIMIT_AS is not set
As reported in issue #724, openbsd fails to build in haproxy.c
due to a faulty comma in the middle of a warning message. This code
is only compiled when RLIMIT_AS is not defined, which seems to be
rare these days.

This may be backported to older versions as the problem was likely
introduced when strict limits were added.
2020-07-02 15:38:35 +02:00
Willy Tarreau
42abe68f11 BUG/MEDIUM: cli/proxy: don't try to dump idle connection state if there's none
Commit 69f591e3b ("MINOR: cli/proxy: add a new "show servers conn" command")
added the ability to dump the idle connections state for a server, but we
must not do this if idle connections were not allocated, which happens if
the server is configured with pool-max-conn 0.

This is 2.2, no backport is needed.
2020-07-02 15:19:57 +02:00
Olivier Houchard
48ce6a3ab1 BUG/MEDIUM: muxes: Make sure nobody stole the connection before using it.
In the various timeout functions, make sure nobody stole the connection from
us before attempting to doing anything with it, there's a very small race
condition between the time we access the task context, and the time we
actually check it again with the lock, where it could have been free'd.
2020-07-02 14:17:25 +02:00
Willy Tarreau
54d31170a9 BUG/MAJOR: sched: make sure task_kill() always queues the task
task_kill() may fail to queue a task if this task has never ever run,
because its equivalent (tasklet->list) member has never been "emptied"
since it didn't pass through the LIST_DEL_INIT() that's performed by
run_tasks_from_lists(). This results in these tasks to never be freed.

It happens during the mux takeover since the target task usually is
the timeout task which, by definition, has never run yet.

This fixes commit eb8c2c69f ("MEDIUM: sched: implement task_kill() to
kill a task") which was introduced after 2.2-dev11 and doesn't need to
be backported.
2020-07-02 14:14:00 +02:00
Willy Tarreau
dab586c3a8 BUILD: debug: avoid build warnings with DEBUG_MEM_STATS
Some libcs define strdup() as a macro and cause redefine warnings to
be emitted, so let's first undefine all functions we redefine.
2020-07-02 10:25:01 +02:00
Dragan Dosen
1e3b16f74f MINOR: log-format: allow to preserve spacing in log format strings
Now it's possible to preserve spacing everywhere except in "log-format",
"log-format-sd" and "unique-id-format" directives, where spaces are
delimiters and are merged. That may be useful when the response payload
is specified as a log format string by "lf-file" or "lf-string", or even
for headers or anything else.

In order to merge spaces, a new option LOG_OPT_MERGE_SPACES is applied
exclusively on options passed to function parse_logformat_string().

This patch fixes an issue #701 ("http-request return log-format file
evaluation altering spacing of ASCII output/art").
2020-07-02 10:11:44 +02:00
Willy Tarreau
a6026a0c92 MINOR: debug: add a new "debug dev memstats" command
Now when building with -DDEBUG_MEM_STATS, some malloc/calloc/strdup/realloc
stats are kept per file+line number and may be displayed and even reset on
the CLI using "debug dev memstats". This allows to easily track potential
leakers or abnormal usages.
2020-07-02 09:14:48 +02:00
Dragan Dosen
d1ba552e41 MINOR: 51d: silence a warning about null pointer dereference
This is due to issue #713, that reports null pointer dereference
suspected by coverity.
2020-07-01 23:27:06 +02:00
Willy Tarreau
76cc699017 MINOR: config: add a new tune.idle-pool.shared global setting.
Enables ('on') or disables ('off') sharing of idle connection pools between
threads for a same server. The default is to share them between threads in
order to minimize the number of persistent connections to a server, and to
optimize the connection reuse rate. But to help with debugging or when
suspecting a bug in HAProxy around connection reuse, it can be convenient to
forcefully disable this idle pool sharing between multiple threads, and force
this option to "off". The default is on.

This could have been nice to have during the idle connections debugging,
but it's not too late to add it!
2020-07-01 19:07:37 +02:00
Willy Tarreau
83ca305ddc DOC: configuration: fix alphabetical ordering for tune.pool-{high,low}-fd-ratio
In addition they were in the wrong alphabetical order in the doc. They
were added in 2.0 by commit 88698d966 ("MEDIUM: connections: Add a way
to control the number of idling connections.") so this must be backported
to 2.0.
2020-07-01 18:30:16 +02:00
Willy Tarreau
a8e2d97905 DOC: configuration: add missing index entries for tune.pool-{low,high}-fd-ratio
These two keywords didn't have an entry in the index. They were added in
2.0 by commit 88698d966 ("MEDIUM: connections: Add a way to control the
number of idling connections.") so this must be backported to 2.0.
2020-07-01 18:29:44 +02:00
Olivier Houchard
ff1d0929b8 MEDIUM: connections: Don't use a lock when moving connections to remove.
Make it so we don't have to take a lock while moving a connection from
the idle list to the toremove_list by taking advantage of the MT_LIST.
2020-07-01 17:09:19 +02:00
Olivier Houchard
f8f4c2ef60 CLEANUP: connections: rename the toremove_lock to takeover_lock
This lock was misnamed and a bit confusing. It's only used for takeover
so let's call it takeover_lock.
2020-07-01 17:09:10 +02:00
Olivier Houchard
bbee1f7e78 MINOR: list: Add MT_LIST_DEL_SAFE_NOINIT() and MT_LIST_ADDQ_NOCHECK()
Add two new macros, MT_LIST_DEL_SAFE_NOINIT makes sure we remove the
element from the list, without reinitializing its next and prev, and
MT_LIST_ADDQ_NOCHECK is similar to MT_LIST_ADDQ(), except it doesn't check
if the element is already in a list.
The goal is to be able to move an element from a list we're currently
parsing to another, keeping it locked in the meanwhile.
2020-07-01 17:04:00 +02:00
Willy Tarreau
88d18f81ae MEDIUM: mux-fcgi: use task_kill() during fcgi_takeover() instead of task_wakeup()
task_wakeup() passes the task through the global run queue under the
global RQ lock, which is expensive when dealing with large amounts of
fcgi_takeover() calls. Let's use the new task_kill() instead to kill the
task.
2020-07-01 16:47:12 +02:00
Willy Tarreau
617e80ff76 MEDIUM: mux-h2: use task_kill() during h2_takeover() instead of task_wakeup()
task_wakeup() passes the task through the global run queue under the
global RQ lock, which is expensive when dealing with large amounts of
h2_takeover() calls. Let's use the new task_kill() instead to kill the
task.
2020-07-01 16:47:12 +02:00
Willy Tarreau
09e0d9ecbc MEDIUM: mux-h1: use task_kill() during h1_takeover() instead of task_wakeup()
task_wakeup() passes the task through the global run queue under the
global RQ lock, which is expensive when dealing with large amounts of
h1_takeover() calls. Let's use the new task_kill() instead to kill the
task.

By doing so, a scenario involving approximately 130k takeover/s running on
16 threads gained almost 3% performance from 319k req/s to 328k.
2020-07-01 16:42:05 +02:00
Willy Tarreau
eb8c2c69fa MEDIUM: sched: implement task_kill() to kill a task
task_kill() may be used by any thread to kill any task with less overhead
than a regular wakeup. In order to achieve this, it bypasses the priority
tree and inserts the task directly into the shared tasklets list, cast as
a tasklet. The task_list_size is updated to make sure it is properly
decremented after execution of this task. The task will thus be picked by
process_runnable_tasks() after checking the tree and sent to the TL_URGENT
list, where it will be processed and killed.

If the task is bound to more than one thread, its first thread will be the
one notified.

If the task was already queued or running, nothing is done, only the flag
is added so that it gets killed before or after execution. Of course it's
the caller's responsibility to make sur any resources allocated by this
task were already cleaned up or taken over.
2020-07-01 16:35:53 +02:00
Willy Tarreau
8a6049c268 MEDIUM: sched: create a new TASK_KILLED task flag
This flag, when set, will be used to indicate that the task must die.
At the moment this may only be placed by the task itself or by the
scheduler when placing it into the TL_NORMAL queue.
2020-07-01 16:35:49 +02:00
Willy Tarreau
d99177f86d MINOR: sched: make sched->task_list_size atomic
We'll need to update it from foreign threads in order to throw killed
tasks and maintain correct accounting, so let's make it atomic.
2020-07-01 16:35:41 +02:00
Willy Tarreau
364f25a688 MINOR: backend: don't always takeover from the same threads
The next thread walking algorithm in commit 566df309c ("MEDIUM:
connections: Attempt to get idle connections from other threads.")
proved to be sufficient for most cases, but it still has some rough
edges when threads are unevenly loaded. If one thread wakes up with
10 streams to process in a burst, it will mainly take over connections
from the next one until it doesn't have anymore.

This patch implements a rotating index that is stored into the server
list and that any thread taking over a connection is responsible for
updating. This way it starts mostly random and avoids always picking
from the same place. This results in a smoother distribution overall
and a slightly lower takeover rate.
2020-07-01 16:07:43 +02:00
Willy Tarreau
0d587116c2 BUG/MEDIUM: backend: always search in the safe list after failing on the idle one
There's a tricky behavior that was lost when the idle connections were
made sharable between thread in commit 566df309c ("MEDIUM: connections:
Attempt to get idle connections from other threads."), it is the ability
to retry from the safe list when looking for any type of idle connection
and not finding one in the idle list.

It is already important when dealing with long-lived connections since
they ultimately all become safe, but that case is already covered by
the fact that safe conns not being used end up closing and are not
looked up anymore since connect_server() sees there are none.

But it's even more important when using server-side connections which
periodically close, because the new connections may spend half of their
time in safe state and the other half in the idle state, and failing
to grab one such connection from the right list results in establishing
a new connection.

This patch makes sure that a failure to find an idle connection results
in a new attempt at finding one from the safe list if available. In order
to avoid locking twice, connections are attempted alternatively from the
idle then safe list when picking from siblings. Tests have shown a ~2%
performance increase by avoiding to lock twice.

A typical test with 10000 connections over 16 threads with 210 servers
having a 1 millisecond response time and closing every 5 requests shows
a degrading performance starting at 120k req/s down to 60-90k and an
average reuse rate of 44%. After the fix, the reuse rate raises to 79%
and the performance becomes stable at 254k req/s. Similarly the previous
test with full keep-alive has now increased from 96% reuse rate to 99%
and from 352k to 375k req/s.

No backport is needed as this is 2.2-only.
2020-07-01 15:49:21 +02:00
Willy Tarreau
2f3f4d3441 MEDIUM: server: add a new pool-low-conn server setting
The problem with the way idle connections currently work is that it's
easy for a thread to steal all of its siblings' connections, then release
them, then it's done by another one, etc. This happens even more easily
due to scheduling latencies, or merged events inside the same pool loop,
which, when dealing with a fast server responding in sub-millisecond
delays, can really result in one thread being fully at work at a time.

In such a case, we perform a huge amount of takeover() which consumes
CPU and requires quite some locking, sometimes resulting in lower
performance than expected.

In order to fight against this problem, this patch introduces a new server
setting "pool-low-conn", whose purpose is to dictate when it is allowed to
steal connections from a sibling. As long as the number of idle connections
remains at least as high as this value, it is permitted to take over another
connection. When the idle connection count becomes lower, a thread may only
use its own connections or create a new one. By proceeding like this even
with a low number (typically 2*nbthreads), we quickly end up in a situation
where all active threads have a few connections. It then becomes possible
to connect to a server without bothering other threads the vast majority
of the time, while still being able to use these connections when the
number of available FDs becomes low.

We also use this threshold instead of global.nbthread in the connection
release logic, allowing to keep more extra connections if needed.

A test performed with 10000 concurrent HTTP/1 connections, 16 threads
and 210 servers with 1 millisecond of server response time showed the
following numbers:

   haproxy 2.1.7:           185000 requests per second
   haproxy 2.2:             314000 requests per second
   haproxy 2.2 lowconn 32:  352000 requests per second

The takeover rate goes down from 300k/s to 13k/s. The difference is
further amplified as the response time shrinks.
2020-07-01 15:23:15 +02:00
Willy Tarreau
35e30c9670 BUG/MINOR: server: fix the connection release logic regarding nearly full conditions
There was a logic bug in commit ddfe0743d ("MEDIUM: server: use the two
thresholds for the connection release algorithm"): instead of keeping
only our first idle connection when FDs become scarce, the condition was
inverted resulting in enforcing this constraint unless FDs are scarce.
This results in less idle connections than permitted to be kept under
normal condition.

No backport needed.
2020-07-01 14:14:29 +02:00
Willy Tarreau
151c253a1e MINOR: server: skip servers with no idle conns earlier
In conn_backend_get() we can avoid locking other servers when trying
to steal their connections when we know for sure they will not have
one, so let's do it to lower the contention on the lock.
2020-07-01 10:33:39 +02:00
Willy Tarreau
69f591e3b0 MINOR: cli/proxy: add a new "show servers conn" command
This command reuses the existing "show servers state" to also dump the
state of active and idle connections. The main use is to serve as a
debugging tool to troubleshot connection reuse issues.
2020-07-01 10:32:54 +02:00
Willy Tarreau
df2a0305f2 BUG/MINOR: proxy: always initialize the trash in show servers state
Actually the cleanup in commit 6ff8143f7 ("BUG/MINOR: proxy: fix
dump_server_state()'s misuse of the trash") allowed to spot that the
trash is never reset when dumping a servers state. I couldn't manage
to make it dump garbage even with large setups but didn't find either
where it's cleared between successive calls while other handlers do
explicitly invoke chunk_reset(), so it seems to happen a bit by luck.

Let's use chunk_printf() here for each turn, it makes things clearer.

This could be backported along with previous patch, especially if any
user reports occasional garbage appearing in the show servers output.
2020-07-01 07:11:14 +02:00
Willy Tarreau
6ff8143f7c BUG/MINOR: proxy: fix dump_server_state()'s misuse of the trash
dump_server_state() claims to dump into a buffer but instead it writes
into a buffer then dumps the trash into the channel, so it only supports
being called with buf=&trash and doesn't need this buffer. There doesn't
seem to be any current impact of this mistake since the function is called
from one location only.

A backport may be performed if it helps fixing other bugs but it will not
fix an existing bug by itself.
2020-07-01 07:02:42 +02:00
Dragan Dosen
2866acfb23 BUG/MEDIUM: log-format: fix possible endless loop in parse_logformat_string()
This patch adds a missing break to end the loop in case when '%[' is not
properly closed with ']'.

The issue has been introduced with commit cd0d2ed ("MEDIUM: log-format:
make the LF parser aware of sample expressions' end").
2020-07-01 06:30:50 +02:00
Christopher Faulet
b4cf7ab9bc BUG/MEDIUM: pattern: Add a trailing \0 to match strings only if possible
In pat_match_str() and pat_math_beg() functions, a trailing zero is
systematically added at the end of the string, even if the buffer is not large
enough to accommodate it. It is a possible buffer overflow. For instance, when
the alpn is matched against a list of strings, the sample fetch is filled with a
non-null terminated string returned by the SSL library. No trailing zero must be
added at the end of this string, because it is outside the buffer.

So, to fix the bug, a trailing zero is added only if the buffer is large enough
to accommodate it. Otherwise, the sample fetch is duplicated. smp_dup() function
adds a trailing zero to the duplicated string, truncating it if it is too long.

This patch should fix the issue #718. It must be backported to all supported
versions.
2020-06-30 19:16:47 +02:00