[PATCH] base static allocations on physical memory size (1 of 7)

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
#   2005/01/14 13:10:38-06:00 [email protected] 
#   JFS: base static allocations on physical memory size
#   
#   On larger systems, performance is improved with a larger
#   allocation of tlocks & tblocks.  Base the default size of these
#   allocations on the physical memory size.
#   
#   Signed-off-by: Dave Kleikamp <[email protected]>
# 
diff -Nru a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
--- a/fs/jfs/jfs_txnmgr.c	2005-02-18 17:01:53 -06:00
+++ b/fs/jfs/jfs_txnmgr.c	2005-02-18 17:01:53 -06:00
@@ -93,15 +93,15 @@
 } TxStat;
 #endif
 
-static int nTxBlock = 512;	/* number of transaction blocks */
+static int nTxBlock = -1;	/* number of transaction blocks */
 module_param(nTxBlock, int, 0);
 MODULE_PARM_DESC(nTxBlock,
-		 "Number of transaction blocks (default:512, max:65536)");
+		 "Number of transaction blocks (max:65536)");
 
-static int nTxLock = 4096;	/* number of transaction locks */
+static int nTxLock = -1;	/* number of transaction locks */
 module_param(nTxLock, int, 0);
 MODULE_PARM_DESC(nTxLock,
-		 "Number of transaction locks (default:4096, max:65536)");
+		 "Number of transaction locks (max:65536)");
 
 struct tblock *TxBlock;	        /* transaction block table */
 static int TxLockLWM;		/* Low water mark for number of txLocks used */
@@ -249,6 +249,25 @@
 int txInit(void)
 {
 	int k, size;
+	struct sysinfo si;
+
+	/* Set defaults for nTxLock and nTxBlock if unset */
+
+	if (nTxLock == -1) {
+		if (nTxBlock == -1) {
+			/* Base default on memory size */
+			si_meminfo(&si);
+			if (si.totalram > (256 * 1024)) /* 1 GB */
+				nTxLock = 64 * 1024;
+			else
+				nTxLock = si.totalram >> 2;
+		} else if (nTxBlock > (8 * 1024))
+			nTxLock = 64 * 1024;
+		else
+			nTxLock = nTxBlock << 3;
+	}
+	if (nTxBlock == -1)
+		nTxBlock = nTxLock >> 3;
 
 	/* Verify tunable parameters */
 	if (nTxBlock < 16)
@@ -259,6 +278,9 @@
 		nTxLock = 256;	/* No one should set it this low */
 	if (nTxLock > 65536)
 		nTxLock = 65536;
+
+	printk(KERN_INFO "JFS: nTxBlock = %d, nTxLock = %d\n",
+	       nTxBlock, nTxLock);
 	/*
 	 * initialize transaction block (tblock) table
 	 *
@@ -266,8 +288,8 @@
 	 * tid = 0 is reserved.
 	 */
 	TxLockLWM = (nTxLock * 4) / 10;
-	TxLockHWM = (nTxLock * 8) / 10;
-	TxLockVHWM = (nTxLock * 9) / 10;
+	TxLockHWM = (nTxLock * 7) / 10;
+	TxLockVHWM = (nTxLock * 8) / 10;
 
 	size = sizeof(struct tblock) * nTxBlock;
 	TxBlock = (struct tblock *) vmalloc(size);