code: mafs

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the minimum number of memunits is a multiple of Ncollisions and the minimum number of hash buckets

--- a/mafs.c

+++ b/mafs.c

@@ -18,7 +18,7 @@

 static void

 usage(void)

 {

-	fprint(2, "usage: mafs [-Ds] [-r service] [-n service] [-m nmemunits] [-h nbuckets] file\n");

+	fprint(2, "usage: mafs [-Ds] [-r service] [-n service] [-m nmemunits] file\n");

 	exits("usage");

 }

@@ -51,7 +51,6 @@

 	default:	usage();

 	case 'D':	chatty9p++; break;

 	case 'f':	devfile = ARGF(); break;

-	case 'h':	nbuckets = atoll(EARGF(usage())); break;

 	case 'm':	nmemunits = atoll(EARGF(usage())); break;

 	case 'r':

 		doream = 1;

@@ -76,16 +75,19 @@

 	if(size == 0)

 		panic("null size %s", devfile);

+	/*

+		Minimum number of collisions = 3

+		Minimum number of hash buckets = 7

+		Minimum number of memunits = 7 * 3 * 2048 blocks = 43,008 blocks

+	 */

 	if(nmemunits == 0){

 		nmemunits = size/Blocksize;

 		if(nmemunits > 8*MiB)

 			nmemunits = 8*MiB;

-		else if(nmemunits < 8*KiB)

-			nmemunits = 8*KiB;

+		else if(nmemunits < 42*KiB)

+			nmemunits = 42*KiB;

 	}

-	/* TODO need to do this better */

-	if(nbuckets == 0)

-		nbuckets = nmemunits/(4*Ncollisions*Maxdatablockunits);

+	nbuckets = nmemunits/(4*Ncollisions*Maxdatablockunits);

 	if(nbuckets < 7)

 		nbuckets = 7;