From e649432e7234dfe6905f4663bd0ce7b37ef2c5e7 Mon Sep 17 00:00:00 2001 From: Daniel Stenberg Date: Sun, 14 Apr 2019 23:20:01 +0200 Subject: CURLOPT_MAXAGE_CONN: set the maximum allowed age for conn reuse ... and disconnect too old ones instead of trying to reuse. Default max age is set to 118 seconds. Ref: #3722 Closes #3782 --- docs/TODO | 11 ------ docs/libcurl/curl_easy_setopt.3 | 2 + docs/libcurl/opts/CURLOPT_MAXAGE_CONN.3 | 65 +++++++++++++++++++++++++++++++++ docs/libcurl/opts/Makefile.inc | 1 + docs/libcurl/symbols-in-versions | 1 + include/curl/curl.h | 3 ++ lib/conncache.c | 5 ++- lib/setopt.c | 6 +++ lib/url.c | 23 +++++++++++- lib/urldata.h | 3 ++ 10 files changed, 106 insertions(+), 14 deletions(-) create mode 100644 docs/libcurl/opts/CURLOPT_MAXAGE_CONN.3 diff --git a/docs/TODO b/docs/TODO index c51a90206..912eefc1a 100644 --- a/docs/TODO +++ b/docs/TODO @@ -35,7 +35,6 @@ 1.16 Try to URL encode given URL 1.17 Add support for IRIs 1.18 try next proxy if one doesn't work - 1.19 Timeout idle connections from the pool 1.20 SRV and URI DNS records 1.21 Have the URL API offer IDN decoding 1.22 CURLINFO_PAUSE_STATE @@ -373,16 +372,6 @@ https://github.com/curl/curl/issues/896 -1.19 Timeout idle connections from the pool - - libcurl currently keeps connections in its connection pool for an indefinite - period of time, until it either gets reused, gets noticed that it has been - closed by the server or gets pruned to make room for a new connection. - - To reduce overhead (especially for when we add monitoring of the connections - in the pool), we should introduce a timeout so that connections that have - been idle for N seconds get closed. - 1.20 SRV and URI DNS records Offer support for resolving SRV and URI DNS records for libcurl to know which diff --git a/docs/libcurl/curl_easy_setopt.3 b/docs/libcurl/curl_easy_setopt.3 index fc361d80c..1f18a3494 100644 --- a/docs/libcurl/curl_easy_setopt.3 +++ b/docs/libcurl/curl_easy_setopt.3 @@ -468,6 +468,8 @@ Maximum number of connections in the connection pool. See \fICURLOPT_MAXCONNECTS Use a new connection. \fICURLOPT_FRESH_CONNECT(3)\fP .IP CURLOPT_FORBID_REUSE Prevent subsequent connections from re-using this. See \fICURLOPT_FORBID_REUSE(3)\fP +.IP CURLOPT_MAXAGE_CONN +Limit the age of connections for reuse. See \fICURLOPT_MAXAGE_CONN(3)\fP .IP CURLOPT_CONNECTTIMEOUT Timeout for the connection phase. See \fICURLOPT_CONNECTTIMEOUT(3)\fP .IP CURLOPT_CONNECTTIMEOUT_MS diff --git a/docs/libcurl/opts/CURLOPT_MAXAGE_CONN.3 b/docs/libcurl/opts/CURLOPT_MAXAGE_CONN.3 new file mode 100644 index 000000000..f91bf7a8d --- /dev/null +++ b/docs/libcurl/opts/CURLOPT_MAXAGE_CONN.3 @@ -0,0 +1,65 @@ +.\" ************************************************************************** +.\" * _ _ ____ _ +.\" * Project ___| | | | _ \| | +.\" * / __| | | | |_) | | +.\" * | (__| |_| | _ <| |___ +.\" * \___|\___/|_| \_\_____| +.\" * +.\" * Copyright (C) 2019, Daniel Stenberg, , et al. +.\" * +.\" * This software is licensed as described in the file COPYING, which +.\" * you should have received as part of this distribution. The terms +.\" * are also available at https://curl.haxx.se/docs/copyright.html. +.\" * +.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell +.\" * copies of the Software, and permit persons to whom the Software is +.\" * furnished to do so, under the terms of the COPYING file. +.\" * +.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY +.\" * KIND, either express or implied. +.\" * +.\" ************************************************************************** +.\" +.TH CURLOPT_MAXAGE_CONN 3 "18 Apr 2019" "libcurl 7.65.0" "curl_easy_setopt options" +.SH NAME +CURLOPT_MAXAGE_CONN \- max idle time allowed for reusing a connection +.SH SYNOPSIS +#include + +CURLcode curl_easy_setopt(CURL *handle, CURLOPT_MAXAGE_CONN, long maxage); +.SH DESCRIPTION +Pass a long as parameter containing \fImaxage\fP - the maximum time in seconds +that you allow an existing connection to have to be considered for reuse for +this request. + +The "connection cache" that holds previously used connections. When a new +request is to be done, it will consider any connection that matches for +reuse. The \fICURLOPT_MAXAGE_CONN(3)\fP limit prevents libcurl from trying +very old connections for reuse, since old connections have a high risk of not +working and thus trying them is a performance loss and sometimes service loss +due to the difficulties to figure out the situation. If a connection is found +in the cache that is older than this set \fImaxage\fP, it will instead be +closed. +.SH DEFAULT +Default maxage is 118 seconds. +.SH PROTOCOLS +All +.SH EXAMPLE +.nf +CURL *curl = curl_easy_init(); +if(curl) { + curl_easy_setopt(curl, CURLOPT_URL, "http://example.com"); + + /* only allow 30 seconds idle time */ + curl_easy_setopt(curl, CURLOPT_MAXAGE_CONN, 30L); + + curl_easy_perform(curl); +} +.fi +.SH AVAILABILITY +Added in libcurl 7.65.0 +.SH RETURN VALUE +Returns CURLE_OK. +.SH "SEE ALSO" +.BR CURLOPT_TIMEOUT "(3), " CURLOPT_FORBID_REUSE "(3), " +.BR CURLOPT_FRESH_CONNECT "(3), " diff --git a/docs/libcurl/opts/Makefile.inc b/docs/libcurl/opts/Makefile.inc index 07547503b..c8e15a5ed 100644 --- a/docs/libcurl/opts/Makefile.inc +++ b/docs/libcurl/opts/Makefile.inc @@ -189,6 +189,7 @@ man_MANS = \ CURLOPT_MAIL_AUTH.3 \ CURLOPT_MAIL_FROM.3 \ CURLOPT_MAIL_RCPT.3 \ + CURLOPT_MAXAGE_CONN.3 \ CURLOPT_MAXCONNECTS.3 \ CURLOPT_MAXFILESIZE.3 \ CURLOPT_MAXFILESIZE_LARGE.3 \ diff --git a/docs/libcurl/symbols-in-versions b/docs/libcurl/symbols-in-versions index 0f43aee31..36c510139 100644 --- a/docs/libcurl/symbols-in-versions +++ b/docs/libcurl/symbols-in-versions @@ -463,6 +463,7 @@ CURLOPT_LOW_SPEED_TIME 7.1 CURLOPT_MAIL_AUTH 7.25.0 CURLOPT_MAIL_FROM 7.20.0 CURLOPT_MAIL_RCPT 7.20.0 +CURLOPT_MAXAGE_CONN 7.65.0 CURLOPT_MAXCONNECTS 7.7 CURLOPT_MAXFILESIZE 7.10.8 CURLOPT_MAXFILESIZE_LARGE 7.11.0 diff --git a/include/curl/curl.h b/include/curl/curl.h index b1184fab5..75f780cd7 100644 --- a/include/curl/curl.h +++ b/include/curl/curl.h @@ -1918,6 +1918,9 @@ typedef enum { /* alt-svc cache file name to possibly read from/write to */ CINIT(ALTSVC, STRINGPOINT, 287), + /* maximum age of a connection to consider it for reuse (in seconds) */ + CINIT(MAXAGE_CONN, LONG, 288), + CURLOPT_LASTENTRY /* the last unused */ } CURLoption; diff --git a/lib/conncache.c b/lib/conncache.c index 39302ba7b..535091996 100644 --- a/lib/conncache.c +++ b/lib/conncache.c @@ -434,6 +434,7 @@ bool Curl_conncache_return_conn(struct connectdata *conn) struct connectdata *conn_candidate = NULL; conn->data = NULL; /* no owner anymore */ + conn->lastused = Curl_now(); /* it was used up until now */ if(maxconnects > 0 && Curl_conncache_size(data) > maxconnects) { infof(data, "Connection cache is full, closing the oldest one.\n"); @@ -479,7 +480,7 @@ Curl_conncache_extract_bundle(struct Curl_easy *data, if(!CONN_INUSE(conn) && !conn->data) { /* Set higher score for the age passed since the connection was used */ - score = Curl_timediff(now, conn->now); + score = Curl_timediff(now, conn->lastused); if(score > highscore) { highscore = score; @@ -537,7 +538,7 @@ Curl_conncache_extract_oldest(struct Curl_easy *data) if(!CONN_INUSE(conn) && !conn->data) { /* Set higher score for the age passed since the connection was used */ - score = Curl_timediff(now, conn->now); + score = Curl_timediff(now, conn->lastused); if(score > highscore) { highscore = score; diff --git a/lib/setopt.c b/lib/setopt.c index 1df38fbb4..594303eff 100644 --- a/lib/setopt.c +++ b/lib/setopt.c @@ -2645,6 +2645,12 @@ static CURLcode vsetopt(struct Curl_easy *data, CURLoption option, return CURLE_BAD_FUNCTION_ARGUMENT; data->set.upkeep_interval_ms = arg; break; + case CURLOPT_MAXAGE_CONN: + arg = va_arg(param, long); + if(arg < 0) + return CURLE_BAD_FUNCTION_ARGUMENT; + data->set.maxage_conn = arg; + break; case CURLOPT_TRAILERFUNCTION: #ifndef CURL_DISABLE_HTTP data->set.trailer_callback = va_arg(param, curl_trailer_callback); diff --git a/lib/url.c b/lib/url.c index 8aefd1583..ad8aa6996 100644 --- a/lib/url.c +++ b/lib/url.c @@ -541,6 +541,7 @@ CURLcode Curl_init_userdefined(struct Curl_easy *data) set->fnmatch = ZERO_NULL; set->upkeep_interval_ms = CURL_UPKEEP_INTERVAL_DEFAULT; set->maxconnects = DEFAULT_CONNCACHE_SIZE; /* for easy handles */ + set->maxage_conn = 118; set->http09_allowed = TRUE; set->httpversion = #ifdef USE_NGHTTP2 @@ -958,6 +959,25 @@ static void prune_dead_connections(struct Curl_easy *data) } } +/* A connection has to have been idle for a shorter time than 'maxage_conn' to + be subject for reuse. The success rate is just too low after this. */ + +static bool conn_maxage(struct Curl_easy *data, + struct connectdata *conn, + struct curltime now) +{ + if(!conn->data) { + timediff_t idletime = Curl_timediff(now, conn->lastused); + idletime /= 1000; /* integer seconds is fine */ + + if(idletime/1000 > data->set.maxage_conn) { + infof(data, "Too old connection (%ld seconds), disconnect it\n", + idletime); + return TRUE; + } + } + return FALSE; +} /* * Given one filled in connection struct (named needle), this function should * detect if there already is one that has all the significant details @@ -981,6 +1001,7 @@ ConnectionExists(struct Curl_easy *data, bool foundPendingCandidate = FALSE; bool canmultiplex = IsMultiplexingPossible(data, needle); struct connectbundle *bundle; + struct curltime now = Curl_now(); #ifdef USE_NTLM bool wantNTLMhttp = ((data->state.authhost.want & @@ -1044,7 +1065,7 @@ ConnectionExists(struct Curl_easy *data, /* connect-only connections will not be reused */ continue; - if(extract_if_dead(check, data)) { + if(conn_maxage(data, check, now) || extract_if_dead(check, data)) { /* disconnect it */ (void)Curl_disconnect(data, check, /* dead_connection */TRUE); continue; diff --git a/lib/urldata.h b/lib/urldata.h index 22a8e6dda..8f7742082 100644 --- a/lib/urldata.h +++ b/lib/urldata.h @@ -866,6 +866,7 @@ struct connectdata { struct curltime now; /* "current" time */ struct curltime created; /* creation time */ + struct curltime lastused; /* when returned to the connection cache */ curl_socket_t sock[2]; /* two sockets, the second is used for the data transfer when doing FTP */ curl_socket_t tempsock[2]; /* temporary sockets for happy eyeballs */ @@ -1553,6 +1554,8 @@ struct UserDefined { long accepttimeout; /* in milliseconds, 0 means no timeout */ long happy_eyeballs_timeout; /* in milliseconds, 0 is a valid value */ long server_response_timeout; /* in milliseconds, 0 means no timeout */ + long maxage_conn; /* in seconds, max idle time to allow a connection that + is to be reused */ long tftp_blksize; /* in bytes, 0 means use default */ curl_off_t filesize; /* size of file to upload, -1 means unknown */ long low_speed_limit; /* bytes/second */ -- cgit v1.2.3