Hi!,
Sometime ago, I wrote that when we send TERM to imapd (although it would
happen with any other I assume, pop, sieve...) procceses we wanted to
exit, due to a user request for disconnecting his/her sessions,
sometimes happened that was like, after that sessions disconnection
(TERM to imapd processes) no enough processes where become spawned
newly. Only sometimes when very few processes needed to be killed.
I have been able to reproduce it. If a user has connected (because
proctitle() has set it in the name) and later in very few time "leaves"
(logouts for instance) and then the process moves to READY state if you
kill with TERM more than MAX_READY_FAILS units of that process in less
than MAX_READY_FAIL_INTERVAL, master won't spawn new processes as it's
written in master.c in lines near 1100 in reap_child() function.
It's suggested to launch a SIGHUP to master for activating again the
service, but it can't be enabled again because the service seems to have
removed from the s data structure but not stopped. Due to that non
process stop, when new imapd attemps to load (in service_create() ) it
can't be created because the socket is still in use.
So, for ensuring this is correct, I have written the following patch for
master.c and that I tested on 3.0.15 :
root@debugcyrus:/usr/ports/mail/cyrus-imapd30 # diff -u
work/cyrus-imapd-3.0.15/master/master.c /master.c-definitivo
--- work/cyrus-imapd-3.0.15/master/master.c 2021-03-09
04:27:45.000000000 +0100
+++ /master.c-definitivo 2024-09-10 18:36:49.797581000 +0200
@@ -129,6 +129,11 @@
};
static int verbose = 0;
+
+/* RESET MAX_READY_FAILS OF SERVICE IN MASTER WRAPPER */
+static int gotsigurg = 0;
+/* RESET MAX_READY_FAILS OF SERVICE IN MASTER WRAPPER */
+
static int listen_queue_backlog = 32;
static int pidfd = -1;
@@ -1047,6 +1052,22 @@
}
}
+/* RESET MAX_READY_FAILS OF SERVICE IN MASTER WRAPPER */
+static void sigurg_handler(int sig __attribute__((unused)))
+{
+ syslog(LOG_DEBUG, "URG CAPTURADO!!!!!!");
+
+ if (gotsigurg)
+ {
+ gotsigurg = 0;
+ }
+ else
+ {
+ gotsigurg = 1;
+ }
+}
+/* RESET MAX_READY_FAILS OF SERVICE IN MASTER WRAPPER */
+
static void reap_child(void)
{
int status;
@@ -1094,10 +1115,24 @@
"terminated abnormally",
SERVICEPARAM(s->name),
SERVICEPARAM(s->familyname), pid);
- if (now - s->lastreadyfail >
MAX_READY_FAIL_INTERVAL) {
+
+ syslog(LOG_DEBUG, "Senal URG vale....
--%d--",gotsigurg);
+
+ if ((now - s->lastreadyfail >
MAX_READY_FAIL_INTERVAL) || (gotsigurg))
+ {
s->nreadyfails = 0;
+
+ if (gotsigurg)
+ {
+ syslog(LOG_DEBUG, "RESETEANDO....");
+ syslog(LOG_DEBUG, "RESETEADO....");
+ }
}
+
+ syslog(LOG_DEBUG, "too many failures for
service %s/%s, resetting counters due to SIGURG received in Cyrus
master. El got vale
--%d--",SERVICEPARAM(s->name),SERVICEPARAM(s->familyname),gotsigurg);
+
s->lastreadyfail = now;
+
if (++s->nreadyfails >= MAX_READY_FAILS &&
s->exec) {
syslog(LOG_ERR, "too many failures for "
"service %s/%s, disabling until next
SIGHUP",
@@ -1305,11 +1340,18 @@
sigemptyset(&action.sa_mask);
action.sa_handler = sighup_handler;
+
#ifdef SA_RESTART
action.sa_flags |= SA_RESTART;
#endif
if (sigaction(SIGHUP, &action, NULL) < 0)
fatalf(1, "unable to install signal handler for SIGHUP: %m");
+
+ /* RESET MAX_READY_FAILS OF SERVICE IN MASTER WRAPPER */
+ action.sa_handler = sigurg_handler;
+ if (sigaction(SIGURG, &action, NULL) < 0)
+ fatalf(1, "unable to install signal handler for SIGURG: %m");
+ /* RESET MAX_READY_FAILS OF SERVICE IN MASTER WRAPPER */
action.sa_handler = sigalrm_handler;
if (sigaction(SIGALRM, &action, NULL) < 0)
root@debugcyrus:/usr/ports/mail/cyrus-imapd30 #
So by what I have seen Cyrus wrapper is written (and the way it handles
services), I think that the possible solutions could be :
* Send a kill(pid,SIGTERM) for ensuring the process die before
forgetting from s structure.
* Do something similar as I have done, which gives you a time window
for having more failures than expected for some seconds and which later
could be undone with for instance the same signal sending.
Reproduced and something proposed at least.
What do you think about it? :)
Cheers!
Egoitz Aurrekoetxea
Departamento de sistemas
94 - 420 94 70 | ego...@sarenet.es
S A R E N E T S.A.U.
Parque Tecnol��gico. Edificio 103 | 48170 Zamudio (Bizkaia) - www.sarenet.es
Antes de imprimir este correo electr��nico piense si es necesario hacerlo.
------------------------------------------
Cyrus: Devel
Permalink:
https://cyrus.topicbox.com/groups/devel/Tf9f7cf579fff1397-M680416b69496188584fe2064
Delivery options: https://cyrus.topicbox.com/groups/devel/subscription
