In ("BUG/MEDIUM: stats: Rely on a local trash buffer to dump the stats"),
we forgot to apply the patch in resolvers.c which provides the
stats_dump_resolvers() function that is involved when dumping with "resolvers"
domain.
As a consequence, resolvers dump was broken because stats_dump_one_line(),
which is used in stats_dump_resolv_to_buffer(), implicitely uses trash_chunk
from stats.c to prepare the dump, and stats_putchk() is then called with
global trash (currently empty) as output data.
Given that trash_dump variable is static and thus only available within stats.c
we change stats_putchk() function prototype so that the function does not take
the output buffer as an argument. Instead, stats_putchk() will implicitly use
the local trash_dump variable declared in stats.c.
It will also prevent further mixups between stats_dump_* functions and
stats_putchk().
This needs to be backported with ("BUG/MEDIUM: stats: Rely on a local trash
buffer to dump the stats")
In ("BUG/MINOR: stats: use proper buffer size for http dump"),
we used trash.size as source buffer size before applying the htx
overhead computation.
It is safer to use res->buf.size instead since res_htx (which is <htx> argument
passed to stats_putchk() in http context) is made from res->buf:
in http_stats_io_handler:
| res_htx = htx_from_buf(&res->buf);
This will prevent the hang bug from showing up again if res->buf.size were to be
less than trash.size (which is set according to tune.bufsize).
This should be backported with ("BUG/MINOR: stats: use proper buffer size for http dump")
The maxconn is set per bind line so let's move it there. This might
possibly even slightly reduce inter-thread contention since this one
is read-mostly and it was stored next to nbconn which changes for
each connection setup or teardown.
Add cum_sess_ver[] new array of counters to count the number of cumulated
HTTP sessions by version (h1, h2 or h3).
Implement proxy_inc_fe_cum_sess_ver_ctr() to increment these counter.
This function is called each a HTTP mux is correctly initialized. The QUIC
must before verify the application operations for the mux is for h3 before
calling proxy_inc_fe_cum_sess_ver_ctr().
ST_F_SESS_OTHER stat field for the cumulated of sessions others than
HTTP sessions is deduced from ->cum_sess_ver counter (for all the session,
not only HTTP sessions) from which the HTTP sessions counters are substracted.
Add cum_req[] new array of counters to count the number of cumulated HTTP
requests by version and others than HTTP requests. This new member replace ->cum_req.
Modify proxy_inc_fe_req_ctr() which increments these counters to pass an HTTP
version, 0 special values meaning "other than an HTTP request". This is the case
for instance for syslog.c from which proxy_inc_fe_req_ctr() is called with 0
as version parameter.
ST_F_REQ_TOT stat field compputing for the cumulated number of requests is modified
to count the sum of all the cum_req[] counters.
As this patch is useful for QUIC, it must be backported to 2.7.
In an attempt to fix GH #1873, ("BUG/MEDIUM: stats: Rely on a local trash
buffer to dump the stats") explicitly reduced output buffer size to leave
enough space for htx overhead under http context.
Github user debtsandbooze, who first reported the issue, came back to us
and said he was still able to make the http dump "hang" with the new fix.
After some tests, it became clear that htx_add_data_atonce() could fail from
time to time in stats_putchk(), even if htx was completely empty:
In http context, buffer size is maxed out at channel_htx_recv_limit().
Unfortunately, channel_htx_recv_limit() is not what we're looking for here
because limit() doesn't compute the proper htx overhead.
Using buf_room_for_htx_data() instead of channel_htx_recv_limit() to compute
max "usable" data space seems to be the last piece of work required for
the previous fix to work properly.
This should be backported everywhere the aforementioned commit is.
During multiple tests we've already noticed that shared stats counters
have become a real bottleneck under large thread counts. With QUIC it's
pretty visible, with qc_snd_buf() taking 2.5% of the CPU on a 48-thread
machine at only 25 Gbps, and this CPU is entirely spent in the atomic
increment of the byte count and byte rate. It's also visible in H1/H2
but slightly less since we're working with larger buffers, hence less
frequent updates. These counters are exclusively used to report the
byte count in "show info" and the byte rate in the stats.
Let's move them to the thread_ctx struct and make the stats reader
just collect each thread's stats when requested. That's way more
efficient than competing on a single cache line.
After this, qc_snd_buf has totally disappeared from the perf profile
and tests made in h1 show roughly 1% performance increase on small
objects.
CF_READ_NULL flag is not really useful and used. It is a transient event
used to wakeup the stream. As we will see, all read events on a channel may
be resumed to only one and are all used to wake up the stream.
In this patch, we introduce CF_READ_EVENT flag as a replacement to
CF_READ_NULL. There is no breaking change for now, it is just a
rename. Gradually, other read events will be merged with this one.
The same change was already performed for the cli. The stats applet and the
prometheus exporter are also concerned. Both use the stats API and rely on
pool functions to get total pool usage in bytes. pool_total_allocated() and
pool_total_used() must return 64 bits unsigned integer to avoid any wrapping
around 4G.
This may be backported to all versions.
It is possible to block the stats applet if a line exceeds the free space in
the responsse buffer while the buffer is empty. It is only an issue in HTTP
becaues of the HTX overhead and, AFAIK, only with json output.
In this case, the applet is unable to write anything in the response buffer
and waits for some free space to proceed further. On the other hand, because
the response channel is empty, nothing is sent and thus no space can be
freed. At this stage, the stream and the applet are blocked waiting for the
other side.
To avoid this situation, we must take care to not dump a line exceeding the
free space in the HTX message. It means we cannot rely anymore on the global
trash buffer. At least, not directly. The trick is to use a local trash
buffer, mapped on the global one but with a different size. We use b_make()
to do so. The local trash buffer is thread local to avoid any concurrency
issue.
It is a valid fix. However it could be good to review the internal API of
the stats applet to not rely on a global variable.
This patch should solve the #1873. It must be backported at least as far as
2.6. Older versions must be evaluated first but it is probably possible to
hit this bug with long proxy/server names.
This is a follow up of "BUG/MINOR: stats: fix show stat json buffer limitation"
However this time this is purely preemptive as we did not reach the buffer
limitation yet. But now is the proper time so that this won't be an issue
in the upcoming versions.
No backport needed.
json output type is a lot more verbose than other output types.
Because of this and the increasing number of metrics implemented within
haproxy, we are starting to reach max bufsize limit (defaults to 16k)
when dumping stats to json since 2.6-dev1.
This results in stats output being truncated with
"[{"errorStr":"output buffer too short"}]"
This was reported by Gabriel in #1964.
Thanks to "MINOR: stats: introduce stats field ctx", we can now make
multipart (using multiple buffers) dumping, in case a single buffer is not big
enough to hold the complete stat line.
For now, only stats_dump_fields_json() makes use of it as it is by
far the most verbose stats output type.
(csv, typed and html outputs should be good for a while and may use this
capability if the need arises in some distant future)
--
It could be backported to 2.6 and 2.7.
This commit depends on:
- MINOR: stats: provide ctx for dumping functions
- MINOR: stats: introduce stats field ctx
Add a new value in stats ctx: field.
Implement field support in line dumping parent functions
stats_print_proxy_field_json() and stats_dump_proxy_to_buffer().
This will allow child dumping functions to support partial line dumping
when needed. ie: when dumping buffer is exhausted: do a partial send and
wait for a new buffer to finish the dump. Thanks to field ctx, the function
can start dumping where it left off on previous (unterminated) invokation.
This is a minor refactor to allow stats_dump_info_* and stats_dump_fields_*
functions to directly access stat ctx pointer instead of explicitly
passing stat ctx struct members to them.
This will allow dumping functions to benefit from upcoming ctx updates.
This patch introduces haproxy_backend_agg_check_status metric
as we wanted in 42d7c402d but with the right data source.
This patch could be backported as far as 2.4.
haproxy_backend_agg_server_check_status currently aggregates
haproxy_server_status instead of haproxy_server_check_status.
We deprecate this and create a new one,
haproxy_backend_agg_server_status to clarify what it really
does.
This patch could be backported as far as 2.4.
ST_F_CHECK_DURATION metric is typed as unsigned int variable, and it is
derived from check->duration that is signed.
While most of the time check->duration > 0, it is not always true:
with HCHK_STATUS_HANA checks, check->duration is set to -1 to prevent server
logs from including irrelevant duration info (HCHK_STATUS_HANA checks are not
time related).
Because of this, stats could report UINT64_MAX value for ST_F_CHECK_DURATION
metric. This was quite confusing. To prevent this, we make sure not to assign
negative value to ST_F_CHECK_DURATION.
This is only a minor printing issue, not backport needed.
Make use of the new srv->rid value in stats.
Stat is referred as ST_F_SRID, it is now used in stats_fill_sv_stats
function in order to be included in csv and json stats dumps.
Moreover, "rid: $value" will be displayed next to server puid
in html stats page if "stats show-legend" is specified in the stats frontend.
(mouse hovering tooltip)
Depends on the following commit:
"MINOR: server: add srv->rid (revision id) value"
This patch adresses the issue #1626.
Adding support for PR_FL_PAUSED flag in the function stats_fill_fe_stats().
The command 'show stat' now properly reports a disabled frontend
using "PAUSED" state label.
This patch depends on the following commits:
- 7d00077fd5 "BUG/MEDIUM: proxy: ensure pause_proxy()
and resume_proxy() own PROXY_LOCK".
- 001328873c "MINOR: listener: small API change"
- d46f437de6 "MINOR: proxy/listener: support for additional PAUSED state"
It should be backported to 2.6, 2.5 and 2.4
This is the continuation of commit 5a0e7ca5d ("BUG/MINOR: cli/stats: add
missing trailing LF after JSON outputs"). There's also a "show info json"
command which was also missing the trailing LF. It's constructed exactly
like the "show stat json", in that it dumps a series of fields without any
LF. The difference however is that for the stats output, everything was
enclosed in an array which required an LF *after* the closing bracket,
while here there's no such array so we have to emit the LF after the loop.
That makes the two functions a bit inconsistent, it's quite annoying, but
making them better would require sending one LF per line in the stats
output, which is not particularly interesting.
Given that it took 5+ years to spot that this code wasn't working as
expected it doesn't seem worth investing much time trying to refactor
it to make it look cleaner at the risk of breaking other obscure parts.
Patrick Hemmer reported that we have a bug in the CLI commands
"show stat json" and "show schema json" in that they forget the trailing
LF that's required to mark the end of the response. This has been the
case since the introduction of the feature in 1.8-dev1 by commit 6f6bb380e
("MEDIUM: stats: Add show json schema"), so this fix may be backported to
all versions.
Function arguments and local variables called "cs" were renamed to "sc"
to avoid future confusion. Both the core functions and the ones in the
resolvers files were updated.
There's no more reason for keepin the code and definitions in conn_stream,
let's move all that to stconn. The alphabetical ordering of include files
was adjusted.
This file contains all the stream-connector functions that are specific
to application layers of type stream. So let's name it accordingly so
that it's easier to figure what's located there.
The alphabetical ordering of include files was preserved.
These ones are essentially for the stream endpoint, let's give them a
name that matches the intent. Equivalent versions were provided in the
applet namespace to ease code legibility.
The new name mor eclearly indicates that a stream connector cannot make
any more progress because it needs room in the channel buffer, or that
it may be unblocked because the buffer now has more room available. The
testing function is sc_waiting_room(). This is mostly used by applets.
Note that the flags will change soon.
These functions return the app-layer associated with an stconn, which
is a check, a stream or a stream's task. They're used a lot to access
channels, flags and for waking up tasks. Let's just name them
appropriately for the stream connector.
We're starting to propagate the stream connector's new name through the
API. Most call places of these functions that retrieve the channel or its
buffer are in applets. The local variable names are not changed in order
to keep the changes small and reviewable. There were ~92 uses of cs_ic(),
~96 of cs_oc() (due to co_get*() being less factorizable than ci_put*),
and ~5 accesses to the buffer itself.
This applies the change so that the applet code stops using ci_putchk()
and friends everywhere possible, for the much saferapplet_put*() instead.
The change is mechanical but large. Two or three functions used to have no
appctx and a cs derived from the appctx instead, which was a reminiscence
of old times' stream_interface. These were simply changed to directly take
the appctx. No sensitive change was performed, and the old (more complex)
API is still usable when needed (e.g. the channel is already known).
The change touched roughly a hundred of locations, with no less than 124
lines removed.
It's worth noting that the stats applet, the oldest of the series, could
get a serious lifting, as it's still very channel-centric instead of
propagating the appctx along the chain. Given that this code doesn't
change often, there's no emergency to clean it up but it would look
better.
This also follows the natural naming. There are roughly 238 changes, all
totally trivial. conn_stream-t.h has become completely void of any
"conn_stream" related stuff now (except its name).
This renames the "struct conn_stream" to "struct stconn" and updates
the descriptions in all comments (and the rare help descriptions) to
"stream connector" or "connector". This touches a lot of files but
the change is minimal. The local variables were not even renamed, so
there's still a lot of "cs" everywhere.
Now at least it makes it obvious that it's the stream endpoint descriptor
and not an endpoint. There were few changes thanks to the previous refactor
of the flags.
This changes all main uses of endp->flags to the se_fl_*() equivalent
by applying coccinelle script endp_flags.cocci. The se_fl_*() functions
themselves were manually excluded from the change, of course.
Note: 144 locations were touched, manually reviewed and found to be OK.
The script was applied with all includes:
spatch --in-place --recursive-includes -I include --sp-file $script $files
This one is the pointer to the conn_stream which is always in the
endpoint that is always present in the appctx, thus it's not needed.
This patch removes it and replaces it with appctx_cs() instead. A
few occurences that were using __cs_strm(appctx->owner) were moved
directly to appctx_strm() which does the equivalent.
The few applets that set CS_EP_EOI or CS_EP_ERROR used to set it on the
endpoint retrieved from the conn_stream while it's already available on
the appctx itself. Better use the appctx one to limit the unneeded
interactions between the two sides.
The STAT_ST_* values have been abused by virtually every applet and CLI
keyword handler, and this must not continue as it's a source of bugs and
of overly complicated code.
This patch renames the states to STAT_STATE_*, and keeps the previous
enum while marking each entry as deprecated. This should be sufficient to
catch out-of-tree code that might rely on them and to let them know what
to do with that.
This makes use of the generic command context allocation so that the
appctx doesn't have to declare a specific one anymore. The context is
created during parsing (both in the CLI and HTTP).
The change looks large but it's particularly mechanical. The context
initialization appears in stats.c and http_ana.c. The context is used
in stats.c and resolvers.c since "show stat resolvers" points there.
That's the reason why the definition moved to stats.h. "show info"
and "show stat" continue to share the same state definition for now.
Nothing else was modified.
There were plenty of leftovers from old code that were never removed
and that are not needed at all since these files do not use any
definition depending on fcntl.h, let's drop them.
Remaining flags and associated functions are move in the conn-stream
scope. These flags are added on the endpoint and not the conn-stream
itself. This way it will be possible to get them from the mux or the
applet. The functions to get or set these flags are renamed accordingly with
the "cs_" prefix and updated to manipualte a conn-stream instead of a
stream-interface.
si_shutr(), si_shutw(), si_chk_rcv() and si_chk_snd() are moved in the
conn-stream scope and renamed, respectively, cs_shutr(), cs_shutw(),
cs_chk_rcv(), cs_chk_snd() and manipulate a conn-stream instead of a
stream-interface.
The stream-interface state (SI_ST_*) is now in the conn-stream. It is a
mechanical replacement for now. Nothing special. SI_ST_* and SI_SB_* were
renamed accordingly. Utils functions to manipulate these infos were moved
under the conn-stream scope.
But it could be good to keep in mind that this part should be
reworked. Indeed, at the CS level, we only need to know if it is ready to
receive or to send. The state of conn-stream from INI to EST is only used on
the server side. The client CS is immediately set to EST. Thus current
SI_ST_* states should probably be moved to the stream to reflect the server
connection state during the establishment stage.
At many places, we now use the new CS functions to get a stream or a channel
from a conn-stream instead of using the stream-interface API. It is the
first step to reduce the scope of the stream-interfaces. The main change
here is about the applet I/O callback functions. Before the refactoring, the
stream-interface was the appctx owner. Thus, it was heavily used. Now, as
far as possible,the conn-stream is used. Of course, it remains many calls to
the stream-interface API.
All old flags CS_FL_* are now moved in the endpoint scope and renamed
CS_EP_* accordingly. It is a systematic replacement. There is no true change
except for the health-check and the endpoint reset. Here it is a bit special
because the same conn-stream is reused. Thus, we must handle endpoint
allocation errors. To do so, cs_reset_endp() has been adapted.
Thanks to this last change, it will now be possible to simplify the
multiplexer and probably the applets too. A review must also be performed to
remove some flags in the channel or the stream-interface. The HTX will
probably be simplified too. Finally, there is now some place in the
conn-stream to move info from the stream-interface.
Shawn Heisey reported that the proxy's description was unreadable in dark
color scheme. This is because the text color is changed in the table but
not the cell's background.
This should be backported to 2.5.
