From 210f5429678dba06f361b1f37bcb946f27e2e20b Mon Sep 17 00:00:00 2001 From: Arturo Borrero Gonzalez Date: Mon, 12 Jun 2017 10:34:35 +0200 Subject: conntrackd: make the daemon run in RT mode by default In order to prevent netlink buffer overrun, conntrackd is recommended to run at max priority. Make conntrackd to use a RT (SHED_RR) scheduler by default at max priority. This is common among other HA daemons. For example corosync uses SCHED_RR by default. The scheduler configuration option is kept in order to allow admins to perform fine-tuning, but it is deleted from example configuration files. Note that this default sched priority is so high that it makes the nice value useless, so deprecate the nice configuration. Anyway the nice value can be set externally at runtime using nice/renice. The code is moved to the init() routine. In case of error setting the scheduler, the system default will be used. Report a message to the user and continue working. Signed-off-by: Arturo Borrero Gonzalez Signed-off-by: Pablo Neira Ayuso --- conntrackd.conf.5 | 35 ++++++++++++----------------------- doc/helper/conntrackd.conf | 21 --------------------- doc/stats/conntrackd.conf | 19 ------------------- doc/sync/alarm/conntrackd.conf | 21 --------------------- doc/sync/ftfw/conntrackd.conf | 21 --------------------- doc/sync/notrack/conntrackd.conf | 21 --------------------- include/conntrackd.h | 1 - src/main.c | 28 ---------------------------- src/read_config_yy.y | 3 ++- src/run.c | 25 +++++++++++++++++++++++++ 10 files changed, 39 insertions(+), 156 deletions(-) diff --git a/conntrackd.conf.5 b/conntrackd.conf.5 index a395e14..2ce6aa3 100644 --- a/conntrackd.conf.5 +++ b/conntrackd.conf.5 @@ -22,7 +22,7 @@ .\" . .\" %%%LICENSE_END .\" -.TH CONNTRACKD.CONF 5 "May 09, 2017" +.TH CONNTRACKD.CONF 5 "June 09, 2017" .SH NAME conntrackd.conf \- configuration file for conntrackd daemon @@ -480,14 +480,10 @@ By default runtime support is disabled. .TP .BI "Nice " -Set the \fBnice(1)\fP value of the daemon, this value goes from -20 (most -favorable scheduling) to 19 (least favorable). Using a very low value reduces -the chances to lose state-change events. - -Example: Nice -20 - -Default is 0 but this example sets it to most favourable scheduling as -this is generally a good idea. +Deprecated. Conntrackd ignores this option and it will be removed in the +future. Please note that you can run \fBnice(1)\fP and \fBrenice(1)\fP +externally. Also note that \fBconntrackd(8)\fP now uses by default a RT +scheduler. .TP .BI "HashSize " @@ -731,8 +727,9 @@ Example: Select a different scheduler for the daemon, you can select between \fBRR\fP and \fBFIFO\fP and the process priority. -See \fBsched_setscheduler(2)\fP for more information. Using a RT scheduler -reduces the chances to overrun the Netlink buffer. +Using a RT scheduler reduces the chances to overrun the Netlink buffer and +\fBconntrackd(8)\fP uses by default \fBRR\fP unless \fBFIFO\fP is selected. +See \fBsched_setscheduler(2)\fP for more information. Example: .nf @@ -746,12 +743,15 @@ Example: .BI "Type " Supported values are \fBRR\fP or \fBFIFO\fP. +Default: RR + .TP .BI "Priority " Value of the scheduler priority. - Minimum is 0, maximum is 99. +Default: 99 (as returned by \fBsched_get_priority_max(2)\fP for \fBSCHED_RR\fP) + .SH STATS This top-level section indicates \fBconntrackd(8)\fP to work as a statistic collector for the nf_conntrack linux kernel subsystem. @@ -904,7 +904,6 @@ Stats { } General { Systemd on - Nice -1 HashSize 8192 HashLimit 65535 Syslog on @@ -969,11 +968,6 @@ Sync { } General { Systemd on - Nice -20 - Scheduler { - Type FIFO - Priority 99 - } HashSize 32768 HashLimit 131072 LogFile on @@ -1031,11 +1025,6 @@ Sync { } General { Systemd on - Nice -20 - Scheduler { - Type FIFO - Priority 99 - } HashSize 32768 HashLimit 131072 LogFile on diff --git a/doc/helper/conntrackd.conf b/doc/helper/conntrackd.conf index 1746bfd..4148544 100644 --- a/doc/helper/conntrackd.conf +++ b/doc/helper/conntrackd.conf @@ -102,27 +102,6 @@ Helper { # General settings # General { - # - # Set the nice value of the daemon, this value goes from -20 - # (most favorable scheduling) to 19 (least favorable). Using a - # very low value reduces the chances to lose state-change events. - # Default is 0 but this example file sets it to most favourable - # scheduling as this is generally a good idea. See man nice(1) for - # more information. - # - Nice -20 - - # - # Select a different scheduler for the daemon, you can select between - # RR and FIFO and the process priority (minimum is 0, maximum is 99). - # See man sched_setscheduler(2) for more information. Using a RT - # scheduler reduces the chances to overrun the Netlink buffer. - # - # Scheduler { - # Type FIFO - # Priority 99 - # } - # # Logfile: on (/var/log/conntrackd.log), off, or a filename # Default: off diff --git a/doc/stats/conntrackd.conf b/doc/stats/conntrackd.conf index 99453ee..ba957a1 100644 --- a/doc/stats/conntrackd.conf +++ b/doc/stats/conntrackd.conf @@ -10,25 +10,6 @@ General { # #Systemd on - # - # Set the nice value of the daemon. This value goes from -20 - # (most favorable scheduling) to 19 (least favorable). Using a - # negative value reduces the chances to lose state-change events. - # Default is 0. See man nice(1) for more information. - # - Nice -1 - - # - # Select a different scheduler for the daemon, you can select between - # RR and FIFO and the process priority (minimum is 0, maximum is 99). - # See man sched_setscheduler(2) for more information. Using a RT - # scheduler reduces the chances to overrun the Netlink buffer. - # - # Scheduler { - # Type FIFO - # Priority 99 - # } - # # Number of buckets in the caches: hash table # diff --git a/doc/sync/alarm/conntrackd.conf b/doc/sync/alarm/conntrackd.conf index e25c30e..831be15 100644 --- a/doc/sync/alarm/conntrackd.conf +++ b/doc/sync/alarm/conntrackd.conf @@ -225,27 +225,6 @@ General { # #Systemd on - # - # Set the nice value of the daemon, this value goes from -20 - # (most favorable scheduling) to 19 (least favorable). Using a - # very low value reduces the chances to lose state-change events. - # Default is 0 but this example file sets it to most favourable - # scheduling as this is generally a good idea. See man nice(1) for - # more information. - # - Nice -20 - - # - # Select a different scheduler for the daemon, you can select between - # RR and FIFO and the process priority (minimum is 0, maximum is 99). - # See man sched_setscheduler(2) for more information. Using a RT - # scheduler reduces the chances to overrun the Netlink buffer. - # - # Scheduler { - # Type FIFO - # Priority 99 - # } - # # Number of buckets in the cache hashtable. The bigger it is, # the closer it gets to O(1) at the cost of consuming more memory. diff --git a/doc/sync/ftfw/conntrackd.conf b/doc/sync/ftfw/conntrackd.conf index bcbf631..9da0fb6 100644 --- a/doc/sync/ftfw/conntrackd.conf +++ b/doc/sync/ftfw/conntrackd.conf @@ -248,27 +248,6 @@ General { # #Systemd on - # - # Set the nice value of the daemon, this value goes from -20 - # (most favorable scheduling) to 19 (least favorable). Using a - # very low value reduces the chances to lose state-change events. - # Default is 0 but this example file sets it to most favourable - # scheduling as this is generally a good idea. See man nice(1) for - # more information. - # - Nice -20 - - # - # Select a different scheduler for the daemon, you can select between - # RR and FIFO and the process priority (minimum is 0, maximum is 99). - # See man sched_setscheduler(2) for more information. Using a RT - # scheduler reduces the chances to overrun the Netlink buffer. - # - # Scheduler { - # Type FIFO - # Priority 99 - # } - # # Number of buckets in the cache hashtable. The bigger it is, # the closer it gets to O(1) at the cost of consuming more memory. diff --git a/doc/sync/notrack/conntrackd.conf b/doc/sync/notrack/conntrackd.conf index c1ad0b4..600fc89 100644 --- a/doc/sync/notrack/conntrackd.conf +++ b/doc/sync/notrack/conntrackd.conf @@ -287,27 +287,6 @@ General { # #Systemd on - # - # Set the nice value of the daemon, this value goes from -20 - # (most favorable scheduling) to 19 (least favorable). Using a - # very low value reduces the chances to lose state-change events. - # Default is 0 but this example file sets it to most favourable - # scheduling as this is generally a good idea. See man nice(1) for - # more information. - # - Nice -20 - - # - # Select a different scheduler for the daemon, you can select between - # RR and FIFO and the process priority (minimum is 0, maximum is 99). - # See man sched_setscheduler(2) for more information. Using a RT - # scheduler reduces the chances to overrun the Netlink buffer. - # - # Scheduler { - # Type FIFO - # Priority 99 - # } - # # Number of buckets in the cache hashtable. The bigger it is, # the closer it gets to O(1) at the cost of consuming more memory. diff --git a/include/conntrackd.h b/include/conntrackd.h index 1a7ea66..ece7025 100644 --- a/include/conntrackd.h +++ b/include/conntrackd.h @@ -94,7 +94,6 @@ struct ct_conf { int channel_type_global; struct channel_conf channel[MULTICHANNEL_MAX]; struct local_conf local; /* unix socket facilities */ - int nice; int limit; int refresh; int cache_timeout; /* cache entries timeout */ diff --git a/src/main.c b/src/main.c index 0418e30..3b19160 100644 --- a/src/main.c +++ b/src/main.c @@ -31,7 +31,6 @@ #include #include #include -#include #include struct ct_general_state st; @@ -111,15 +110,6 @@ set_action_by_table(int i, int argc, char *argv[], return i; } -static void -set_nice_value(int nv) -{ - errno = 0; - if (nice(nv) == -1 && errno) /* warn only */ - dlog(LOG_WARNING, "Cannot set nice level %d: %s", - nv, strerror(errno)); -} - static void do_chdir(const char *d) { @@ -373,24 +363,6 @@ int main(int argc, char *argv[]) } close(ret); - /* - * Setting process priority and scheduler - */ - set_nice_value(CONFIG(nice)); - - if (CONFIG(sched).type != SCHED_OTHER) { - struct sched_param schedparam = { - .sched_priority = CONFIG(sched).prio, - }; - - ret = sched_setscheduler(0, CONFIG(sched).type, &schedparam); - if (ret == -1) { - dlog(LOG_ERR, "scheduler configuration failed: %s", - strerror(errno)); - exit(EXIT_FAILURE); - } - } - /* * initialization process */ diff --git a/src/read_config_yy.y b/src/read_config_yy.y index 30a8bd4..32cca3c 100644 --- a/src/read_config_yy.y +++ b/src/read_config_yy.y @@ -967,7 +967,8 @@ netlink_events_reliable : T_NETLINK_EVENTS_RELIABLE T_OFF nice : T_NICE T_SIGNED_NUMBER { - conf.nice = $2; + dlog(LOG_WARNING, "deprecated nice configuration, ignoring. The " + "nice value can be set externally with nice(1) and renice(1)."); }; scheduler : T_SCHEDULER '{' scheduler_options '}'; diff --git a/src/run.c b/src/run.c index 1fe6cba..f11a532 100644 --- a/src/run.c +++ b/src/run.c @@ -32,6 +32,7 @@ #include "internal.h" #include "systemd.h" +#include #include #include #include @@ -234,11 +235,35 @@ int evaluate(void) return 0; } + +static void set_scheduler(void) +{ + struct sched_param schedparam; + int sched_type; + + if (CONFIG(sched).type == SCHED_OTHER) { + /* default */ + schedparam.sched_priority = sched_get_priority_max(SCHED_RR); + sched_type = SCHED_RR; + } else { + schedparam.sched_priority = CONFIG(sched).prio; + sched_type = CONFIG(sched).type; + } + + if (sched_setscheduler(0, sched_type, &schedparam) < 0) + dlog(LOG_WARNING, "scheduler configuration failed: %s. " + "Likely a bug in conntrackd, please report it. " + "Continuing with system default scheduler.", + strerror(errno)); +} + int init(void) { do_gettimeofday(); + set_scheduler(); + STATE(fds) = create_fds(); if (STATE(fds) == NULL) { dlog(LOG_ERR, "can't create file descriptor pool"); -- cgit v1.2.3