The remaining contention on the server lock solely comes from
sess_change_server() which takes the lock to add and remove a
stream from the server's actconn list. This is both expensive
and pointless since we have mt-lists, and this list is only
used by the CLI's "shutdown server sessions" command!
Let's migrate to an mt-list and remove the need for this costly
lock. By doing so, the request rate increased by ~1.8%.
The server lock was taken preventively for anything in health_adjust(),
including the static config checks needed to detect that the lock was not
needed, while the function is always called on the response path to update
a server's status. This was responsible for huge contention causing a
performance drop of about 17% on 16 threads. Let's move the lock only
where it should be, i.e. inside the function around the critical sections
only. By doing this, a 16-thread process jumped back from 575 to 675 krps.
This should be backported to 2.3 as the situation degraded there, and
maybe later to 2.2.
There's an issue when a server state changes, we use an integer comparison
to decide whether or not to reschedule a test instead of using a wrapping
timer comparison. This will cause some health-checks not to be immediately
triggered half of the time, and some unneeded calls to task_queue() to be
performed in other cases.
This bug has always been there as it was introduced with the commit that
added the feature, 97f07b832 ("[MEDIUM] Decrease server health based on
http responses / events, version 3"). This may be backported everywhere.
conn_hash_prehash does not need a nul-terminated string, thus it is only
needed to test if the sni sample is not null before using it as
connection hash input.
Moreover, a bug could be introduced between smp_make_safe and
ssl_sock_set_servername call. Indeed, smp_make_safe may call smp_dup
which duplicates the sample in the trash buffer. If another function
manipulates the trash buffer before the call to ssl_sock_set_servername,
the sni sample might be erased. Currently, no function seems to do that
except make_proxy_line in case proxy protocol is used simultaneously
with the sni on the server.
This does not need to be backported.
In session_count_new() the tracked counter was still incremented with
a "++" outside of any lock, resulting in occasional slightly off values
such as the following:
# table: foo, type: string, size:1000, used:1
0xb2a398: key=127.1.2.3 use=0 exp=86398318 sess_cnt=999959 http_req_cnt=1000004
Now with the correct atomic increment:
# table: foo, type: string, size:1000, used:1
0x7f82a4026d38: key=127.1.2.3 use=0 exp=86399294 sess_cnt=1000004 http_req_cnt=1000004
This can be backported to 1.8.
It seems that fd_delete perform the close of the file descriptor
Se we must not close the fd once again after that.
This should fix issues #1128, #1130 and #1131
This patch fix a case which should never happen writing
in output channel since we check available room before
This patch should fix github issue #1132
This patch fix returns code in case of dns_connect_server is called
on unsupported type (which should not happen). Doing this we have
the warranty that after a return 0 the fd is never -1.
This patch should fix github issues #1127, #1128 and #1130
This patch adds a missing test in dns_session_io_handler, getting
the query id from the buffer of the ring. An error should never
happen since messages are completely added atomically.
This bug should fix github issue #1133
move listen status to a helper, defining both status enum and string
definition.
this will be helpful to be reused in prometheus code. It also removes
this hard-to-read nested ternary.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
From this patch it should be possible to add support for listen stats in
prometheus.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
The RMAINT admin state is dynamic and should be remove from the
srv_admin_state parameter when a server state is loaded from a server-state
file. Otherwise an erorr is reported, the server-state line is ignored and
the server state is not updated.
This patch should fix the issue #576. It must be backported as far as 1.8.
This patch introduce the new line "server" to set a TCP
nameserver in a "resolvers" section:
server <name> <address> [param*]
Used to configure a DNS TCP or stream server. This supports for all
"server" parameters found in 5.2 paragraph. Some of these parameters
are irrelevant for DNS resolving. Note: currently 4 queries are pipelined
on the same connections. A batch of idle connections are removed every
5 seconds. "maxconn" can be configured to limit the amount of those
concurrent connections and TLS should also usable if the server supports
. The current implementation limits to 4 pipelined
The name of the line in configuration is open to discussion
and could be changed before the next release.
This patch introduce the "dns_stream_nameserver" to use DNS over
TCP on strict nameservers. For the upper layer it is analog to
the api used with udp nameservers except that the user que switch
the name server in "stream" mode at the init using "dns_stream_init".
The fallback from UDP to TCP is not handled and this is not the
purpose of this feature. This is done to choose the transport layer
during the initialization.
Currently there is a hardcoded limit of 4 pipelined transactions
per TCP connections. A batch of idle connections is expired every 5s.
This code is designed to support a maximum DNS message size on TCP: 64k.
Note: this code won't perform retry on unanswered queries this
should be handled by the upper layer
This patch splits current dns.c into two files:
The first dns.c contains code related to DNS message exchange over UDP
and in future other TCP. We try to remove depencies to resolving
to make it usable by other stuff as DNS load balancing.
The new resolvers.c inherit of the code specific to the actual
resolvers.
Note:
It was really difficult to obtain a clean diff dur to the amount
of moved code.
Note2:
Counters and stuff related to stats is not cleany separated because
currently counters for both layers are merged and hard to separate
for now.
This patch splits recv and send functions in two layers. the
lowest is responsible of DNS message transactions over
the network. Doing this we could use DNS message layer
for something else than resolving. Load balancing for instance.
This patch also re-works the way to init a nameserver and
introduce the new struct dns_dgram_server to prepare the arrival
of dns_stream_server and the support of DNS over TCP.
The way to retry a send failure of a request because of EAGAIN
was re-worked. Previously there was no control and all "pending"
queries were re-played each time it reaches a EAGAIN. This
patch introduce a ring to stack messages in case of sent
failure. This patch is emptied if poller shows that the
socket is ready again to push messages.
Counters are currently stored into lowlevel nameservers struct but
most of them are resolving layer data and increased in the upper layer
So this patch renames the prototype used to allocate/dump them with prefix
'resolv' waiting for a clean split.
Some types are specific to resolver code and a renamed using
the 'resolv' prefix instead 'dns'.
-struct dns_query_item {
+struct resolv_query_item {
-struct dns_answer_item {
+struct resolv_answer_item {
-struct dns_response_packet {
+struct resolv_response {
Resolv callbacks are also updated to rely on counters and not on
nameservers.
"show stat domain dns" will now show the parent id (i.e. resolvers
section name).
FreeBSD has a kernel feature (accf) and a sockopt flag similar to the
Linux's TCP_DEFER_ACCEPT to filter incoming data upon ACK. The main
difference is the filter needs to be placed when the socket actually
listens.
Very often, especially since reg-tests, it would be desirable to be able
to conditionally comment out a config block, such as removing an SSL
binding when SSL is disabled, or enabling HTX only for certain versions,
etc.
This patch introduces a very simple nested block management which takes
".if", ".elif", ".else" and ".endif" directives to take or ignore a block.
For now the conditions are limited to empty string or "0" for false versus
a non-nul integer for true, which already suffices to test environment
variables. Still, it needs to be a bit more advanced with defines, versions
etc.
A set of ".notice", ".warning" and ".alert" statements are provided to
emit messages, often in order to provide advice about how to fix certain
conditions.
The "show peers" output has become huge due to the dictionaries making it
less readable. Now this feature has reached a certain level of maturity
which doesn't warrant to dump it all the time, given that it was essentially
needed by developers. Let's make it optional, and disabled by default, only
when "show peers dict" is requested. The default output reminds about the
command. The output has been divided by 5 :
$ socat - /tmp/sock1 <<< "show peers dict" | wc -l
125
$ socat - /tmp/sock1 <<< "show peers" | wc -l
26
It could be useful to backport this to recent stable versions.
This variable is now only used to point on the local server-state file. When
the server-state is global, it is unused. So, we now use "localfilepath"
instead. Thus, the "filepath" variable can safely be removed.
When a local server-state file is loaded, if its name is too long, the error
is not properly handled, resulting to a call to fopen() with the "filepath"
variable set to NULL. To fix the bug, when this error occurs, we jump to the
next proxy, via a "continue" statement. And we take case to set "filepath"
variable after the error handling to be sure.
This patch should fix the issue #1111. It must be backported as far as 1.6.
When a connect rule is evaluated a test is performed on the "port" variable
while it is set to 0 just on the line just above. Just remove this useless
test to make ccpcheck happy.
This patch fixes the issue #1113.
Now it becomes possible to specify "from foo" on a frontend/listen/backend
or even on a "defaults" line, to mention that defaults section "foo" needs
to be used to preset the proxy's settings.
When not set, the last section remains used. In case the designated name
is found at multiple places, it is rejected and an error indicates two
occurrences of the same name. Similarly, if the section name is found,
its name must only use valid characters. This allows multiple named
defaults section to continue to coexist without the risk that they will
cause trouble by accident.
When it comes to "defaults" relying on another defaults, what happens is
just that a new defaults section is created from the designated one. This
will make it possible for example to reuse some settings such as log-format
like below:
defaults tcp-clear
log stdout local0 info
log-format "%ci:%cp/%b/%si:%sp %ST %ts %U/%B %{+Q}r"
defaults tcp-ssl
log stdout local0 info
log-format "%ci:%cp/%b/%si:%sp %ST %ts %U/%B %{+Q}r ssl=%sslv"
defaults http-clear from tcp-clear
mode http
defaults http-ssl from tcp-ssl
mode http
frontend fe1 from http-clear
bind :8001
frontend fe2 from http-ssl
bind :8002
A small corner case remains in the error detection, if a second defaults
section appears with the same name after the point where it was used, and
nobody references it, the duplicate will not be detected. This could be
addressed by performing the syntactic checks in check_config_validity(),
and by postponing the freeing of the defaults, after tagging a defaults
section as explicitly looked up by another section. This doesn't seem
that important at the moment though.
Now default proxies are stored into a dedicated tree, sorted by name.
Only unnamed entries are not kept upon new section creation. The very
first call to cfg_parse_listen() will automatically allocate a dummy
defaults section which corresponds to the previous static one, since
the code requires to have one at a few places.
The first immediately visible benefit is that it allows to reuse
alloc_new_proxy() to allocate a defaults section instead of doing it by
hand. And the secret goal is to allow to keep multiple named defaults
section in memory to reuse them from various proxies.
Now we'll have a tree of named defaults sections. The regular insertion
and lookup functions take care of the capability in order to select the
appropriate tree. A new function proxy_destroy_defaults() removes a
proxy from this tree and frees it entirely.
In order to make the default proxy configurable, we'll need to have a
pointer to it which might differ from &defproxy. cfg_parse_listen()
now gets curr_defproxy for this.
We don't want to expose this one anymore as we'll soon keep multiple
default proxies. Let's move it inside the parser which is the only
place which still uses it, and initialize it on the fly once needed
instead of doing it at boot time.
The default proxy was passed as a variable, which in addition to being
a PITA to deal with in the config parser, doesn't feel safe to use when
it ought to be const.
This will only affect new code so no backport is needed.
The default proxy was passed as a variable, which in addition to being
a PITA to deal with in the config parser, doesn't feel safe to use when
it ought to be const.
This will only affect new code so no backport is needed.
The default proxy was passed as a variable, which in addition to being
a PITA to deal with in the config parser, doesn't feel safe to use when
it ought to be const.
This will only affect new code so no backport is needed.
