ref: 3b2b18328b6d6e9fb8005c28d8abce59c4bc44e0
parent: a24626c51f894e0976d2eadbcb93cc337a50fafc
author: cinap_lenrek <[email protected]>
date: Thu May 17 22:01:04 EDT 2012
cwfs: add fsmempercent enviroment variable to control iobuffer allocation
--- a/sys/man/4/cwfs
+++ b/sys/man/4/cwfs
@@ -303,6 +303,15 @@
If the label cannot be read,
.I cwfs
will attempt to write a new label.
+.PP
+The original file server reserved the rest of the machines RAM for
+io buffers. Where
+.I cwfs
+running under the Plan 9 kernel reserves a settable percentage
+of the remaining user pages. The percentage is read from the
+enviroment variable
+.B fsmempercent
+which when not set is assumed to be 25% (default).
.SH EXAMPLES
Place the root of the
.B dump
--- a/sys/src/cmd/cwfs/malloc.c
+++ b/sys/src/cmd/cwfs/malloc.c
@@ -4,34 +4,40 @@
static ulong
memsize(void)
{- int nf, pgsize = 0;
- ulong userpgs = 0, userused = 0;
- char *ln, *sl;
- char *fields[2];
+ ulong pgsize, userpgs, userused;
+ char *s, *f[2];
+ int n, mpcnt;
Biobuf *bp;
- bp = Bopen("#c/swap", OREAD);- if (bp != nil) {- while ((ln = Brdline(bp, '\n')) != nil) {- ln[Blinelen(bp)-1] = '\0';
- nf = tokenize(ln, fields, nelem(fields));
- if (nf != 2)
+ mpcnt = 25;
+ pgsize = userpgs = userused = 0;
+ if(bp = Bopen("#c/swap", OREAD)) {+ while(s = Brdline(bp, '\n')) {+ if((n = Blinelen(bp)) < 1)
continue;
- if (strcmp(fields[1], "pagesize") == 0)
- pgsize = atoi(fields[0]);
- else if (strcmp(fields[1], "user") == 0) {- sl = strchr(fields[0], '/');
- if (sl == nil)
- continue;
- userpgs = atol(sl+1);
- userused = atol(fields[0]);
+ s[n-1] = '\0';
+ if(tokenize(s, f, nelem(f)) != 2)
+ continue;
+ if(strcmp(f[1], "pagesize") == 0)
+ pgsize = strtoul(f[0], 0, 0);
+ else if(strcmp(f[1], "user") == 0) {+ userused = strtoul(f[0], &s, 0);
+ if(*s == '/')
+ userpgs = strtoul(s+1, 0, 0);
}
}
Bterm(bp);
- if (pgsize > 0 && userused < userpgs)
- return (userpgs - userused)*pgsize;
}
- return 64*MB;
+ if(pgsize && userused < userpgs){+ if(s = getenv("fsmempercent")){+ mpcnt = atoi(s);
+ free(s);
+ }
+ if(mpcnt < 1)
+ mpcnt = 1;
+ return ((userpgs-userused)*mpcnt/100)*pgsize;
+ }
+ return 16*MB;
}
@@ -65,7 +71,6 @@
void
iobufinit(void)
{- long m;
int i;
char *xiop;
Iobuf *p, *q;
@@ -74,8 +79,7 @@
wlock(&mainlock); /* init */
wunlock(&mainlock);
- m = memsize() / 4;
- niob = m / (sizeof(Iobuf) + RBUFSIZE + sizeof(Hiob)/HWIDTH);
+ niob = memsize() / (sizeof(Iobuf) + RBUFSIZE + sizeof(Hiob)/HWIDTH);
nhiob = niob / HWIDTH;
while(!prime(nhiob))
nhiob++;