Hi,
Pages in the malloc cache are either reused quickly or unmapped
quickly. In both cases it does not make sense to set hints on them.
So remove that option, which is just a remainder of old times when
mallco used to hold on to pages. OK?
-Otto
Index: lib/libc/stdlib/malloc.c
===================================================================
RCS file: /cvs/src/lib/libc/stdlib/malloc.c,v
retrieving revision 1.207
diff -u -p -r1.207 malloc.c
--- lib/libc/stdlib/malloc.c 22 Oct 2016 14:27:19 -0000 1.207
+++ lib/libc/stdlib/malloc.c 28 Oct 2016 08:52:05 -0000
@@ -176,7 +176,6 @@ struct malloc_readonly {
int malloc_mt; /* multi-threaded mode? */
int malloc_freenow; /* Free quickly - disable chunk rnd */
int malloc_freeunmap; /* mprotect free pages PROT_NONE? */
- int malloc_hint; /* call madvice on free pages? */
int malloc_junk; /* junk fill? */
int malloc_move; /* move allocations to end of page? */
int malloc_realloc; /* always realloc? */
@@ -374,8 +373,6 @@ unmap(struct dir_info *d, void *p, size_
MALLOC_MAXCHUNK : sz;
memset(p, SOME_FREEJUNK, amt);
}
- if (mopts.malloc_hint)
- madvise(p, sz, MADV_FREE);
if (mopts.malloc_freeunmap)
mprotect(p, sz, PROT_NONE);
r->p = p;
@@ -447,8 +444,6 @@ map(struct dir_info *d, void *hint, size
d->free_regions_size -= psz;
if (mopts.malloc_freeunmap)
mprotect(p, sz, PROT_READ | PROT_WRITE);
- if (mopts.malloc_hint)
- madvise(p, sz, MADV_NORMAL);
if (zero_fill)
memset(p, 0, sz);
else if (mopts.malloc_junk == 2 &&
@@ -465,8 +460,6 @@ map(struct dir_info *d, void *hint, size
r->p = (char *)r->p + (psz << MALLOC_PAGESHIFT);
if (mopts.malloc_freeunmap)
mprotect(p, sz, PROT_READ | PROT_WRITE);
- if (mopts.malloc_hint)
- madvise(p, sz, MADV_NORMAL);
r->size -= psz;
d->free_regions_size -= psz;
if (zero_fill)
@@ -531,12 +524,6 @@ omalloc_parseopt(char opt)
break;
case 'G':
mopts.malloc_guard = MALLOC_PAGESIZE;
- break;
- case 'h':
- mopts.malloc_hint = 0;
- break;
- case 'H':
- mopts.malloc_hint = 1;
break;
case 'j':
if (mopts.malloc_junk > 0)
Index: share/man/man5/malloc.conf.5
===================================================================
RCS file: /cvs/src/share/man/man5/malloc.conf.5,v
retrieving revision 1.9
diff -u -p -r1.9 malloc.conf.5
--- share/man/man5/malloc.conf.5 17 Oct 2016 06:29:08 -0000 1.9
+++ share/man/man5/malloc.conf.5 28 Oct 2016 08:52:09 -0000
@@ -73,10 +73,6 @@ option for security).
Enable guard pages.
Each page size or larger allocation is followed by a guard page that will
cause a segmentation fault upon any access.
-.It Cm H
-.Dq Hint .
-Pass a hint to the kernel about pages we don't use.
-If the machine is paging a lot this may help a bit.
.It Cm J
.Dq More junking .
Increase the junk level by one if it is smaller than 2.
