mirrors/haproxy
1
0
Fork 0
mirror of https://git.haproxy.org/git/haproxy.git/ synced 2025-08-11 09:37:20 +02:00
Code Issues Projects Releases Wiki Activity
f3338349ec
haproxy/include/common/defaults.h
Willy Tarreau f3338349ec BUG/MEDIUM: counters: flush content counters after each request 
One year ago, commit 5d5b5d8 ("MEDIUM: proto_tcp: add support for tracking
L7 information") brought support for tracking L7 information in tcp-request
content rules. Two years earlier, commit 0a4838c ("[MEDIUM] session-counters:
correctly unbind the counters tracked by the backend") used to flush the
backend counters after processing a request.

While that earliest patch was correct at the time, it became wrong after
the second patch was merged. The code does what it says, but the concept
is flawed. "TCP request content" rules are evaluated for each HTTP request
over a single connection. So if such a rule in the frontend decides to
track any L7 information or to track L4 information when an L7 condition
matches, then it is applied to all requests over the same connection even
if they don't match. This means that a rule such as :

     tcp-request content track-sc0 src if { path /index.html }

will count one request for index.html, and another one for each of the
objects present on this page that are fetched over the same connection
which sent the initial matching request.

Worse, it is possible to make the code do stupid things by using multiple
counters:

     tcp-request content track-sc0 src if { path /foo }
     tcp-request content track-sc1 src if { path /bar }

Just sending two requests first, one with /foo, one with /bar, shows
twice the number of requests for all subsequent requests. Just because
both of them persist after the end of the request.

So the decision to flush backend-tracked counters was not the correct
one. In practice, what is important is to flush countent-based rules
since they are the ones evaluated for each request.

Doing so requires new flags in the session however, to keep track of
which stick-counter was tracked by what ruleset. A later change might
make this easier to maintain over time.

This bug is 1.5-specific, no backport to stable is needed.
2014-01-28 21:40:28 +01:00

220 lines
6.7 KiB
C
Raw Blame History

/*
* include/common/defaults.h
* Miscellaneous default values.
*
* Copyright (C) 2000-2010 Willy Tarreau - w@1wt.eu
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _COMMON_DEFAULTS_H
#define _COMMON_DEFAULTS_H
/*
* BUFSIZE defines the size of a read and write buffer. It is the maximum
* amount of bytes which can be stored by the proxy for each session. However,
* when reading HTTP headers, the proxy needs some spare space to add or rewrite
* headers if needed. The size of this spare is defined with MAXREWRITE. So it
* is not possible to process headers longer than BUFSIZE-MAXREWRITE bytes. By
* default, BUFSIZE=16384 bytes and MAXREWRITE=BUFSIZE/2, so the maximum length
* of headers accepted is 8192 bytes, which is in line with Apache's limits.
*/
#ifndef BUFSIZE
#define BUFSIZE 16384
#endif
// reserved buffer space for header rewriting
#ifndef MAXREWRITE
#define MAXREWRITE (BUFSIZE / 2)
#endif
#ifndef REQURI_LEN
#define REQURI_LEN 1024
#endif
#ifndef CAPTURE_LEN
#define CAPTURE_LEN 64
#endif
// maximum line size when parsing config
#ifndef LINESIZE
#define LINESIZE 2048
#endif
// max # args on a configuration line
#define MAX_LINE_ARGS 64
// max # args on a stats socket
// This should cover at least 5 + twice the # of data_types
#define MAX_STATS_ARGS 64
// max # of matches per regexp
#define MAX_MATCH 10
// max # of headers in one HTTP request or response
// By default, about 100 headers (+1 for the first line)
#ifndef MAX_HTTP_HDR
#define MAX_HTTP_HDR 101
#endif
// max # of headers in history when looking for header #-X
#ifndef MAX_HDR_HISTORY
#define MAX_HDR_HISTORY 10
#endif
// max # of stick counters per session (at least 3 for sc0..sc2)
// Some changes are needed in TCP_ACT_TRK_SC*, SN_BE_TRACK_SC*, and
// SN_CT_TRACK_SC* if more values are required.
#ifndef MAX_SESS_STKCTR
#define MAX_SESS_STKCTR 3
#endif
// max # of loops we can perform around a read() which succeeds.
// It's very frequent that the system returns a few TCP segments at a time.
#ifndef MAX_READ_POLL_LOOPS
#define MAX_READ_POLL_LOOPS 4
#endif
// minimum number of bytes read at once above which we don't try to read
// more, in order not to risk facing an EAGAIN. Most often, if we read
// at least 10 kB, we can consider that the system has tried to read a
// full buffer and got multiple segments (>1 MSS for jumbo frames, >7 MSS
// for normal frames) did not bother truncating the last segment.
#ifndef MIN_RECV_AT_ONCE_ENOUGH
#define MIN_RECV_AT_ONCE_ENOUGH (7*1448)
#endif
// The minimum number of bytes to be forwarded that is worth trying to splice.
// Below 4kB, it's not worth allocating pipes nor pretending to zero-copy.
#ifndef MIN_SPLICE_FORWARD
#define MIN_SPLICE_FORWARD 4096
#endif
// the max number of events returned in one call to poll/epoll. Too small a
// value will cause lots of calls, and too high a value may cause high latency.
#ifndef MAX_POLL_EVENTS
#define MAX_POLL_EVENTS 200
#endif
// cookie delimitor in "prefix" mode. This character is inserted between the
// persistence cookie and the original value. The '~' is allowed by RFC2965,
// and should not be too common in server names.
#ifndef COOKIE_DELIM
#define COOKIE_DELIM '~'
#endif
// this delimitor is used between a server's name and a last visit date in
// cookies exchanged with the client.
#ifndef COOKIE_DELIM_DATE
#define COOKIE_DELIM_DATE '|'
#endif
#define CONN_RETRIES 3
#define CHK_CONNTIME 2000
#define DEF_CHKINTR 2000
#define DEF_FALLTIME 3
#define DEF_RISETIME 2
#define DEF_AGENT_FALLTIME 1
#define DEF_AGENT_RISETIME 1
#define DEF_CHECK_REQ "OPTIONS / HTTP/1.0\r\n"
#define DEF_SMTP_CHECK_REQ "HELO localhost\r\n"
#define DEF_LDAP_CHECK_REQ "\x30\x0c\x02\x01\x01\x60\x07\x02\x01\x03\x04\x00\x80\x00"
#define DEF_REDIS_CHECK_REQ "*1\r\n$4\r\nPING\r\n"
#define DEF_HANA_ONERR HANA_ONERR_FAILCHK
#define DEF_HANA_ERRLIMIT 10
// X-Forwarded-For header default
#define DEF_XFORWARDFOR_HDR "X-Forwarded-For"
// X-Original-To header default
#define DEF_XORIGINALTO_HDR "X-Original-To"
/* Default connections limit.
*
* A system limit can be enforced at build time in order to avoid using haproxy
* beyond reasonable system limits. For this, just define SYSTEM_MAXCONN to the
* absolute limit accepted by the system. If the configuration specifies a
* higher value, it will be capped to SYSTEM_MAXCONN and a warning will be
* emitted. The only way to override this limit will be to set it via the
* command-line '-n' argument.
*/
#ifndef SYSTEM_MAXCONN
#ifndef DEFAULT_MAXCONN
#define DEFAULT_MAXCONN 2000
#endif
#else
#undef DEFAULT_MAXCONN
#define DEFAULT_MAXCONN SYSTEM_MAXCONN
#endif
/* Minimum check interval for spread health checks. Servers with intervals
* greater than or equal to this value will have their checks spread apart
* and will be considered when searching the minimal interval.
* Others will be ignored for the minimal interval and will have their checks
* scheduled on a different basis.
*/
#ifndef SRV_CHK_INTER_THRES
#define SRV_CHK_INTER_THRES 1000
#endif
/* Specifies the string used to report the version and release date on the
* statistics page. May be defined to the empty string ("") to permanently
* disable the feature.
*/
#ifndef STATS_VERSION_STRING
#define STATS_VERSION_STRING " version " HAPROXY_VERSION ", released " HAPROXY_DATE
#endif
/* Maximum signal queue size, and also number of different signals we can
* handle.
*/
#ifndef MAX_SIGNAL
#define MAX_SIGNAL 256
#endif
/* Maximum host name length */
#ifndef MAX_HOSTNAME_LEN
#define MAX_HOSTNAME_LEN 32
#endif
/* Maximum health check description length */
#ifndef HCHK_DESC_LEN
#define HCHK_DESC_LEN 128
#endif
/* ciphers used as defaults on connect */
#ifndef CONNECT_DEFAULT_CIPHERS
#define CONNECT_DEFAULT_CIPHERS NULL
#endif
/* ciphers used as defaults on listeners */
#ifndef LISTEN_DEFAULT_CIPHERS
#define LISTEN_DEFAULT_CIPHERS NULL
#endif
/* named curve used as defaults for ECDHE ciphers */
#ifndef ECDHE_DEFAULT_CURVE
#define ECDHE_DEFAULT_CURVE "prime256v1"
#endif
/* ssl cache size */
#ifndef SSLCACHESIZE
#define SSLCACHESIZE 20000
#endif
#endif /* _COMMON_DEFAULTS_H */
Reference in New Issue View Git Blame Copy Permalink