Prevent the operating system from swapping out the pages of a mom process.
Inspired by a patch from NCSA, but fixed to make sure that children spawned
by the mom do not continue to have all their pages locked too.  Also quite
simplified.


---

 pbs-2.3.12-pw/src/resmom/mom_main.c   |    4 ++++
 pbs-2.3.12-pw/src/resmom/start_exec.c |    6 ++++++
 2 files changed, 10 insertions(+)

diff -puN src/resmom/mom_main.c~mom-mlockall src/resmom/mom_main.c
--- pbs-2.3.12/src/resmom/mom_main.c~mom-mlockall	2004-04-17 11:10:43.000000000 -0400
+++ pbs-2.3.12-pw/src/resmom/mom_main.c	2004-04-17 11:10:43.000000000 -0400
@@ -2193,6 +2193,10 @@ main(argc, argv)
 	add_conn(rppfd, Primary, (pbs_net_t)0, 0, rpp_request);
 	add_conn(privfd, Primary, (pbs_net_t)0, 0, rpp_request);
 
+	/* keep ourselves in memory to avoid getting hurt by the OOM killer */
+	if (mlockall(MCL_CURRENT | MCL_FUTURE))
+	    log_err(errno, id, "mlockall");
+
 	/* initialize machine dependent polling routines */
 	if ((c = mom_open_poll()) != PBSE_NONE) {
 		log_err(c, msg_daemonname, "pre_poll failed");
diff -puN src/resmom/start_exec.c~mom-mlockall src/resmom/start_exec.c
--- pbs-2.3.12/src/resmom/start_exec.c~mom-mlockall	2004-04-17 11:10:43.000000000 -0400
+++ pbs-2.3.12-pw/src/resmom/start_exec.c	2004-04-17 11:10:43.000000000 -0400
@@ -97,6 +97,7 @@
 #include <sys/stat.h>
 #include <sys/socket.h>
 #include <sys/wait.h>
+#include <sys/mman.h>
 #include <netinet/in.h>
 #if IBM_SP2==2	/* IBM SP with PSSP 3.1 */
 #include <st_client.h>
@@ -2076,6 +2077,11 @@ pid_t fork_me(conn)
 
 		(void)mom_close_poll();
 		net_close(conn);	/* close all but for the current */
+
+		/* release mlock; it seems to be inherited even though the
+		 * man page claims otherwise */
+		(void) munlockall();
+
 	} else if (pid < 0)
 		log_err(errno, "fork_me", "fork failed");
 

_