afs: Raise osidnlc NCSIZE

The currrent size of the osi DNLC is very small; only 300 entries.
Raise it to 4096 entries, to give it some chance of actually helping.

In the future, of course, this should be runtime configurable, and we
should also raise the hash table size. For now, just raise the number
of entries without changing anything else, to try to make sure nothing
breaks.

With the hash size of 256, this means our hash chains will be at least
16 items long. However, traversing even hundreds of hash items should
still be better than frequently hitting the disk cache to find
entries, and acquiring more locks, etc.

Change-Id: I48f496e8c25fa869ded83e97ff686ed028c923c5
Reviewed-on: https://gerrit.openafs.org/13531
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>

src/afs/afs_osidnlc.c

@@ -32,7 +32,7 @@ extern struct afs_lock afs_xvcache;
 
 dnlcstats_t dnlcstats;
 
-#define NCSIZE 300
+#define NCSIZE 4096
 #define NHSIZE 256		/* must be power of 2. == NHASHENT in dir package */
 struct nc *ncfreelist = NULL;
 static struct nc nameCache[NCSIZE];