PERFORCE change 104663 for review

[Chris Jones]

http://perforce.freebsd.org/chv.cgi?CH=104663

Change 104663 by cdjones at cdjones-impulse on 2006/08/21 08:35:04

	Mission accomplished: pager thread now stops when it's appropriate.

Affected files ...

.. //depot/projects/soc2006/cdjones_jail/src/sys/kern/kern_jail.c#24 edit
.. //depot/projects/soc2006/cdjones_jail/src/sys/sys/jail.h#20 edit

Differences ...

==== //depot/projects/soc2006/cdjones_jail/src/sys/kern/kern_jail.c#24 (text+ko) ====

@@ -156,17 +156,21 @@
 			break;
 	       
 		if (jail_limit_memory && pr->pr_mem_limit) {
-			/* TODO: consider whether it might be better to start
+			/* 
+			 * TODO: consider whether it might be better to start
 			 * pushing back when we approach the limit, rather than
 			 * when we hit it.
+			 * 
 			 */
-			limit = (long) prison_memory_limit(pr);
-			usage = (long) prison_memory(pr);
+			limit = prison_memory_limit(pr);
+			usage = prison_memory(pr);
 			
-			/* The logic from vm_daemon() really needs to go here.
-			 * Problem: we want to push things below their rlimits.
+			/*
+			 * The logic from vm_daemon() really needs to go here.
+			 * Problem: we want to push things below their rlimits,
+			 * and vm_daemon doesn't do that.  It'd be better to 
+			 * refactor vm_daemon to fit, but this'll do for now.
 			 *
-			 * TODO: refactor vm_daemon to optionally act on specific jails?
 			 */
 			
 			printf("jpager/%d: memory %ld / %ld bytes\n", 
@@ -213,20 +217,23 @@
 					 */      
 					
 					/* TODO: this arbitrarily reduces each process's space by
-					 * 5% (until it's completely swapped out) while
+					 * 6.25% (until it's completely swapped out) while
 					 * we're under memory pressure.  A better way would be 
 					 * to either hit large processes first, or to hit the
 					 * least-active processes first, or go proportionally,
 					 * or .... 
 					 */
-					newsize = cursize = (long) vmspace_resident_count(p->p_vmspace);
-					newsize -= newsize / 20;
+					newsize = cursize = vmspace_resident_count(p->p_vmspace);
+					newsize -= newsize / 16;
 					if (cursize < 0)
 						newsize = 0;
 					PROC_UNLOCK(p);
 					printf("jpager/%d: squeezing process %d from %ld to %ld\n", 
 					       pr_id, p->p_pid, cursize, newsize);
 					vm_pageout_map_deactivate_pages(&p->p_vmspace->vm_map, newsize);
+					printf("jpager/%d: squeezed process %d from %ld to %ld (wanted %ld)\n",
+					       pr_id, p->p_pid, cursize, 
+					       vmspace_resident_count(p->p_vmspace), newsize);
 				} /* end LIST_FOREACH procs */
 				sx_sunlock(&allproc_lock);
 			}
@@ -552,32 +559,31 @@
 }
 
 /* Given credential, return memory usage in bytes. */
-vm_pindex_t
+long
 prison_memory(struct prison *pr)
 {
 	struct proc *p;
-	u_int mem_used = 0;
+	long mem_used = 0;
 	
-	/* TODO: cut this to search only procs in given jail. */
+	/* 
+	 * TODO: this is a really bad way of doing the
+	 * search, as we end up going across all processes
+	 * for each jail.  It'd be more efficient to just do 
+	 * this once in a period and update the relevant jail.
+	 *
+	 */
 	FOREACH_PROC_IN_SYSTEM(p) {
 		if (!jailed(p->p_ucred) ||
-		    (pr != p->p_ucred->cr_prison)) {
+		    (pr != p->p_ucred->cr_prison))
 			continue;
-		}
-		
-		/* Get memory usage (see vm/vm_map.h). */
-		/* TODO maybe use vm_swrss? */
-		mem_used += (p->p_vmspace)->vm_tsize; /* text size (pages) */
-		mem_used += (p->p_vmspace)->vm_dsize; /* data size (pages) */
-		mem_used += (p->p_vmspace)->vm_ssize; /* stack size (pages) */
+		mem_used += vmspace_resident_count(p->p_vmspace);
 	}
-	
-	mem_used *= PAGE_SIZE;
+       	mem_used *= PAGE_SIZE;
 	return mem_used;
 }
 
 /* Given credential, return permitted memory usage in bytes. */
-vm_pindex_t
+long
 prison_memory_limit(struct prison *pr)
 {
 	vm_pindex_t memlimit;

==== //depot/projects/soc2006/cdjones_jail/src/sys/sys/jail.h#20 (text+ko) ====

@@ -134,8 +134,8 @@
 void prison_hold(struct prison *pr);
 int prison_if(struct ucred *cred, struct sockaddr *sa);
 int prison_ip(struct ucred *cred, int flag, u_int32_t *ip);
-vm_pindex_t prison_memory(struct prison *pr);
-vm_pindex_t prison_memory_limit(struct prison *pr);
+long prison_memory(struct prison *pr);
+long prison_memory_limit(struct prison *pr);
 void prison_remote_ip(struct ucred *cred, int flags, u_int32_t *ip);
 
 #endif /* _KERNEL */