Here the timings before the patch:
Script started on Fri Jan 8 13:01:53 1999
root@laser:~# time find / >/dev/null
real 0m1.523s
user 0m0.420s
sys 0m1.100s
root@laser:~# time find / >/dev/null
real 0m1.532s
user 0m0.500s
sys 0m1.050s
root@laser:~# time find / >/dev/null
real 0m1.534s
user 0m0.390s
sys 0m1.140s
root@laser:~# /usr/bin/time find / >/dev/null
0.50user 1.04system 0:01.54elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (83major+32minor)pagefaults 0swaps
root@laser:~# /usr/bin/time find / >/dev/null
0.43user 1.11system 0:01.54elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (83major+32minor)pagefaults 0swaps
root@laser:~# time (find / >/dev/null & find / >/dev/null )
real 0m1.849s
user 0m0.800s
sys 0m2.900s
root@laser:~# time (find / >/dev/null & find / >/dev/null )
real 0m1.807s
user 0m0.870s
sys 0m2.750s
root@laser:~# exit
Script done on Fri Jan 8 13:02:48 1999
Here with the getname-slab-cache patch applyed:
Script started on Fri Jan 8 12:54:55 1999
root@laser:~# time find / >/dev/null
real 0m1.479s
user 0m0.400s
sys 0m1.080s
root@laser:~# time find / >/dev/null
real 0m1.481s
user 0m0.460s
sys 0m1.030s
root@laser:~# time find / >/dev/null
real 0m1.480s
user 0m0.370s
sys 0m1.110s
root@laser:~# /usr/bin/time find / >/dev/null
0.61user 0.87system 0:01.47elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (83major+32minor)pagefaults 0swaps
root@laser:~# /usr/bin/time find / >/dev/null
0.43user 1.05system 0:01.48elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (83major+32minor)pagefaults 0swaps
root@laser:~# /usr/bin/time find / >/dev/null
0.46user 1.02system 0:01.47elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (83major+32minor)pagefaults 0swaps
root@laser:~# time (find / >/dev/null & find / >/dev/null )
real 0m1.746s
user 0m0.980s
sys 0m2.510s
root@laser:~# time (find / >/dev/null & find / >/dev/null )
real 0m1.748s
user 0m0.800s
sys 0m2.700s
Script done on Fri Jan 8 12:56:14 1999
Under normal usage the slabstats looks like this:
caandrea@laser:~$ cat /proc/slabinfo
*snip*
getname_cache 0 6
*snip*
And finally here the patch against 2.2.0-pre5:
Index: fs/namei.c
===================================================================
RCS file: /var/cvs/linux/fs/namei.c,v
retrieving revision 1.1.1.1.2.8
diff -u -r1.1.1.1.2.8 namei.c
--- namei.c 1998/12/29 01:19:03 1.1.1.1.2.8
+++ linux/fs/namei.c 1999/01/08 12:00:55
@@ -16,6 +16,7 @@
#include <linux/proc_fs.h>
#include <linux/smp_lock.h>
#include <linux/quotaops.h>
+#include <linux/init.h>
#include <asm/uaccess.h>
#include <asm/unaligned.h>
@@ -101,6 +102,21 @@
*
* POSIX.1 2.4: an empty pathname is invalid (ENOENT).
*/
+
+/*
+ * Cache the getname buffer in the slab cache to improve performances.
+ * Copyright (C) 1999 Andrea Arcangeli
+ */
+
+static kmem_cache_t * getname_cache;
+
+#define __getname() kmem_cache_alloc(getname_cache, GFP_KERNEL)
+
+void putname(char * name)
+{
+ kmem_cache_free(getname_cache, name);
+}
+
static inline int do_getname(const char *filename, char *page)
{
int retval;
@@ -1303,4 +1319,15 @@
}
unlock_kernel();
return error;
+}
+
+void __init namei_init(void)
+{
+ getname_cache = kmem_cache_create("getname_cache",
+ PAGE_SIZE,
+ 0,
+ SLAB_HWCACHE_ALIGN,
+ NULL, NULL);
+ if (!getname_cache)
+ panic("cannot create getname cache");
}
Index: include/linux/fs.h
===================================================================
RCS file: /var/cvs/linux/include/linux/fs.h,v
retrieving revision 1.1.1.1.2.11
diff -u -r1.1.1.1.2.11 fs.h
--- fs.h 1999/01/03 19:51:15 1.1.1.1.2.11
+++ linux/include/linux/fs.h 1999/01/08 11:37:09
@@ -168,6 +168,7 @@
extern void inode_init(void);
extern void file_table_init(void);
extern void dcache_init(void);
+extern void namei_init(void);
typedef char buffer_block[BLOCK_SIZE];
@@ -697,8 +698,7 @@
extern struct file *filp_open(const char *, int, int);
extern char * getname(const char * filename);
-#define __getname() ((char *) __get_free_page(GFP_KERNEL))
-#define putname(name) free_page((unsigned long)(name))
+extern void FASTCALL(putname(char * name));
extern void kill_fasync(struct fasync_struct *fa, int sig);
extern int register_blkdev(unsigned int, const char *, struct file_operations *);
Index: init/main.c
===================================================================
RCS file: /var/cvs/linux/init/main.c,v
retrieving revision 1.1.1.1.2.10
diff -u -r1.1.1.1.2.10 main.c
--- main.c 1999/01/05 00:18:33 1.1.1.1.2.10
+++ linux/init/main.c 1999/01/08 11:31:13
@@ -1160,6 +1160,7 @@
buffer_init();
signals_init();
inode_init();
+ namei_init();
file_table_init();
#if defined(CONFIG_SYSVIPC)
ipc_init();
Ah and I don't know what does it mean SLAB_RED_ZONE and SLAB_POISON...
-
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