ref: 44ce0097b612a1fefd754065bdf8d9d2e5ef60c8
parent: 099be971bd6e64a23911e1ab666a3f4eec48bcce
author: 9ferno <gophone2015@gmail.com>
date: Tue Aug 31 23:34:21 EDT 2021
avoid reaming all, ream as needed
--- a/appl/cmd/disk/kfs64.b
+++ b/appl/cmd/disk/kfs64.b
@@ -10,6 +10,10 @@
# triple, quadruple, quintiple and sextuple-indirect blocks
# filename size 102 bytes
# using a default bufsize of 512 bytes, small but not too small
+# added halt to shutdown using disk/kfscmd
+# using hwblock to represent the highest touched block number
+# to avoid reaming all the free space at once
+# only ream some more blocks after hwblock, when we need space
include "sys.m";
sys: Sys;
@@ -41,8 +45,8 @@
#
# fundamental constants
#
- # keeping Dentrysize to 512 and 128 bytes for data in Dentry leaves 228 bytes
-NAMELEN: con 102; # ext2, ext3, ext4, zfs - 255 bytes
+ # keeps Dentrysize to 250
+NAMELEN: con 102; # ext2, ext3, ext4, zfs - 255 bytes, kfs - 28, cwfs - 144
NDBLOCK: con 8; # number of direct blocks in Dentry
NIBLOCK: con 6; # max depth of indirect blocks in Dentry - sextuple-indirect blocks
MAXFILESIZE: con big 16r7FFFFFFFFFFFFFFF; # Plan 9's limit (kfs's size is signed)
@@ -152,6 +156,7 @@
fsize: big; # size in blocks
tfree: big; # total number of free blocks
qidgen: big; # generator for unique ids
+ hwblock: big; # highest touched block number, high water block number
fsok: int;
@@ -824,8 +829,6 @@
if(t == nil)
break loop;
else{- if(debug)
- sys->print("<- %s\n", t.text());r := apply(cp, t);
pick m := r {Error =>
@@ -2190,6 +2193,7 @@
# u64 fsize; # total number of blocks on this device
# u64 tfree; # total number of free blocks on this device
# u64 qidgen; # generator for unique ids
+# u64 hwblock; # highest touched block number, high water block number
# s32 fsok; # file system ok
# u64 roraddr; # dump root addr - obsolete, unused in this program
# u64 last; # last super block addr - obsolete, unused in this program
@@ -2199,7 +2203,8 @@
Ofsize: con Ofstart+8;
Otfree: con Ofsize+8;
Oqidgen: con Otfree+8;
-Ofsok: con Oqidgen+8;
+Ohwblock: con Oqidgen+8;
+Ofsok: con Ohwblock+8;
# Ororaddr: con Ofsok+8;
# Olast: con Ororaddr+8;
# Onext: con Olast+8;
@@ -2212,6 +2217,7 @@
s.fsize = get8(a, Ofsize);
s.tfree = get8(a, Otfree);
s.qidgen = get8(a, Oqidgen);
+ s.hwblock = get8(a, Ohwblock);
s.fsok = get4(a, Ofsok);
s.fbuf = a[Super1size:];
return s;
@@ -2223,13 +2229,14 @@
put8(a, Ofsize, s.fsize);
put8(a, Otfree, s.tfree);
put8(a, Oqidgen, s.qidgen);
+ put8(a, Ohwblock, s.hwblock);
put4(a, Ofsok, s.fsok);
}
Superb.print(sb: self ref Superb)
{- sys->print("fstart=%bud fsize=%bud tfree=%bud qidgen=%bud fsok=%d\n",- sb.fstart, sb.fsize, sb.tfree, sb.qidgen, sb.fsok);
+ sys->print("fstart=%bud fsize=%bud tfree=%bud qidgen=%bud hwblock=%bud fsok=%d\n",+ sb.fstart, sb.fsize, sb.tfree, sb.qidgen, sb.hwblock, sb.fsok);
}
Dentry.get(p: ref Iobuf, slot: int): ref Dentry
@@ -2575,7 +2582,7 @@
return addr;
}
-# buffer pool management routines
+# allocate a disk block
balloc(dev: ref Device, tag: int, qpath: big): big
{# TO DO: cache superblock to reduce pack/unpack
@@ -2587,11 +2594,32 @@
sb.tfree--;
if(n < 0 || n >= FEPERBUF)
panic("balloc: bad freelist");+ if(sb.hwblock <= big 0)
+ panic(sys->sprint("balloct bad hwblock <= 0: %bd", sb.hwblock));a := get8(sb.fbuf, 4+n*8);
if(n == 0){ if(a == big 0){+ # out of free space within hwblock blocks
+ # extend hwblock and add those new blocks as free space
+ if(sb.hwblock < sb.fsize-big 1){+ end := sb.hwblock+big FEPERBUF**2;
+ if(end > sb.fsize -big 1)
+ end = sb.fsize -big 1;
+ if(debug)
+ sys->print("balloc: used up all free space, allocating upto %bd\n", end);+ for(i := end; i>sb.hwblock; i--){+ addfree(dev, i, sb);
+ }
+ sb.hwblock = end;
+ sb.touched();
+ sb.print();
+ sb.put();
+ return balloc(dev, tag, qpath);
+ }
sb.tfree = big 0;
sb.touched();
+ if(debug)
+ sb.print();
sb.put();
return big 0;
}
@@ -2621,7 +2649,7 @@
sb.put();
return a;
}
-
+# add a freed block to the list of free blocks
bfree(dev: ref Device, addr: big, d: int)
{if(addr == big 0)
@@ -2651,7 +2679,7 @@
addfree(dev, addr, s);
s.put();
}
-
+# add the freed block to the list of free blocks in super block
addfree(dev: ref Device, addr: big, sb: ref Superb)
{ if(addr >= sb.fsize){@@ -3202,7 +3230,6 @@
fsize := wrensize(dev);
if(fsize <= big 0)
panic("file system device size");- sys->print("kfs: ream %bd blocks ", fsize);p := Iobuf.get(dev, addr, Bmod|Bimm);
p.iobuf[0:] = emptyblock;
p.settag(Tsuper, QPSUPER);
@@ -3212,11 +3239,20 @@
sb.fsize = fsize;
sb.qidgen = big 10;
sb.tfree = big 0;
+ sb.hwblock = big 2; # 0th block left out, super block at 1, root block at 2
sb.fsok = 0;
sb.fbuf = p.iobuf[Super1size:];
put4(sb.fbuf, 0, 1); # nfree = 1
msg := "";
- for(i := fsize-big 1; i>=addr+big 2; i--){+# this is taking forever.
+# Check my notes in the kfs paper and inferno.notes
+# it is more efficient to do this when needed
+# for(i := fsize-big 1; i>=addr+big 2; i--){+ end := sb.fstart+big FEPERBUF**2;
+ if(end > sb.fsize -big 1)
+ end = sb.fsize -big 1;
+ sys->print("kfs: ream %bd out of %bd blocks now:", end, fsize);+ for(i := end; i>=addr+big 2; i--){ #sys->print("superream i %bd\n", i); if(debug){ msg = sys->sprint(" %bd ", i);@@ -3224,6 +3260,7 @@
}
addfree(dev, i, sb); # what does this do?
}
+ sb.hwblock = big end;
sys->print("done\n");sb.put();
}
@@ -3905,7 +3942,9 @@
sb.fbuf[0:] = emptyblock[0:4+FEPERBUF*8];
sb.tfree = big 0;
put4(sb.fbuf, 0, 1); # nfree = 1
- for(a:=sb.fsize-sb.fstart-big 1; a >= big 0; a--){+ if(sb.hwblock <= big 0)
+ panic(sys->sprint("Check.mkfreelist bad hwblock <= 0: %bd", sb.hwblock));+ for(a:=sb.hwblock-sb.fstart-big 1; a >= big 0; a--){i := a>>3;
if(i < big 0 || i >= big len c.amap.bits)
continue;