upas/fs: speedup mtree and henter()

move digest pointer into Mtree structrue and embed it into Idx struct
(which is embedded in Message) to avoid one level of indirection
during mtreecmp().

get rid of mtreeisdup(). instead we have mtreeadd() return the old
message in case of a collision. this avoids double lookup.

increase the hash table size for henter() and make it a prime.

1 files changed, 6 insertions, 3 deletions

diff --git a/sys/src/cmd/upas/fs/cache.c b/sys/src/cmd/upas/fs/cache.c
index 5312886b3..52ed93c79 100644
--- a/sys/src/cmd/upas/fs/cache.c
+++ b/sys/src/cmd/upas/fs/cache.c
@@ -319,14 +319,17 @@ found:
 void
 digestmessage(Mailbox *mb, Message *m)
 {
+	Message *old;
+
 	assert(m->digest == nil);
 	m->digest = emalloc(SHA1dlen);
 	sha1((uchar*)m->start, m->end - m->start, m->digest, nil);
-	if(mtreeisdup(mb, m)){
+	old = mtreeadd(mb, m);
+	if(old != nil && old != m){
+		m = mtreeadd(mb, old);
 		logmsg(m, "dup detected");
 		m->deleted = Dup;	/* no dups allowed */
-	}else
-		mtreeadd(mb, m);
+	}
 	dprint("%lud %#A\n", m->id, m->digest);
 }