------ begin of swap cache patch (search for ------)
diff -u -r linux.orig/include/linux/swap.h linux/include/linux/swap.h
--- linux.orig/include/linux/swap.h Mon Jun 3 14:38:37 1996
+++ linux/include/linux/swap.h Fri Apr 18 17:11:22 1997
@@ -34,6 +34,7 @@
extern int nr_swap_pages;
extern int nr_free_pages;
+extern int nr_swap_cache_pages;
extern atomic_t nr_async_pages;
extern int min_free_pages;
extern int free_pages_low;
@@ -113,10 +114,12 @@
swap_cache_find_total++;
#endif
entry = xchg(swap_cache + index, 0);
+ if (entry) {
#ifdef SWAP_CACHE_INFO
- if (entry)
swap_cache_find_success++;
#endif
+ nr_swap_cache_pages--;
+ }
return entry;
}
@@ -133,6 +136,7 @@
swap_cache_del_success++;
#endif
swap_free(entry);
+ nr_swap_cache_pages--;
return 1;
}
return 0;
diff -u -r linux.orig/mm/mmap.c linux/mm/mmap.c
--- linux.orig/mm/mmap.c Fri Dec 6 22:09:24 1996
+++ linux/mm/mmap.c Fri Apr 18 17:12:08 1997
@@ -55,9 +55,10 @@
long freepages;
freepages = buffermem >> PAGE_SHIFT;
freepages += page_cache_size;
- freepages >>= 1;
+/* freepages >>= 1;*/
freepages += nr_free_pages;
freepages += nr_swap_pages;
+ freepages += nr_swap_cache_pages;
freepages -= MAP_NR(high_memory) >> 4;
return freepages > pages;
}
diff -u -r linux.orig/mm/swap_state.c linux/mm/swap_state.c
--- linux.orig/mm/swap_state.c Wed Mar 13 14:17:23 1996
+++ linux/mm/swap_state.c Fri Apr 18 17:12:11 1997
@@ -32,6 +32,8 @@
*/
unsigned long *swap_cache;
+int nr_swap_cache_pages = 0;
+
#ifdef SWAP_CACHE_INFO
unsigned long swap_cache_add_total = 0;
unsigned long swap_cache_add_success = 0;
@@ -64,6 +66,7 @@
#ifdef SWAP_CACHE_INFO
swap_cache_add_success++;
#endif
+ nr_swap_cache_pages++;
return 1;
}
return 0;
diff -u -r linux.orig/mm/swapfile.c linux/mm/swapfile.c
--- linux.orig/mm/swapfile.c Thu Apr 10 23:47:14 1997
+++ linux/mm/swapfile.c Fri Apr 18 17:12:12 1997
@@ -570,6 +570,7 @@
++val->totalswap;
}
}
+ val->freeswap += nr_swap_cache_pages;
val->freeswap <<= PAGE_SHIFT;
val->totalswap <<= PAGE_SHIFT;
return;
------ end of swap cache patch
------ begin of page cache patch
--- linux.orig/mm/filemap.c.orig Thu Aug 7 11:25:00 1997
+++ linux/mm/filemap.c Thu Aug 7 12:04:02 1997
@@ -157,6 +157,15 @@
switch (page->count) {
case 1:
+#ifdef CONFIG_FREE_PAGE_CACHE
+ /* is it a page cache page? */
+ if (page->inode) {
+ remove_page_from_hash_queue(page);
+ remove_page_from_inode_queue(page);
+ __free_page(page);
+ return 1;
+ }
+#endif
/* If it has been referenced recently, don't free it */
if (clear_bit(PG_referenced, &page->flags)) {
/* age this page potential used */
@@ -165,6 +174,7 @@
break;
}
+#ifndef CONFIG_FREE_PAGE_CACHE
/* is it a page cache page? */
if (page->inode) {
remove_page_from_hash_queue(page);
@@ -172,6 +182,7 @@
__free_page(page);
return 1;
}
+#endif
/* is it a buffer cache page? */
if (bh && try_to_free_buffer(bh, &bh, 6))
@@ -180,7 +191,12 @@
default:
/* more than one users: we can't throw it away */
+#ifdef CONFIG_FREE_PAGE_CACHE
+ if (!clear_bit(PG_referenced, &page->flags))
+ age_page(page);
+#else
set_bit(PG_referenced, &page->flags);
+#endif
/* fall through */
case 0:
/* nothing */
diff -u --recursive --unidirectional-new-file linux.orig/mm/Config.in linux/mm/Config.in
--- linux.orig/mm/Config.in Thu Jan 1 00:00:00 1970
+++ linux/mm/Config.in Thu Aug 7 12:22:14 1997
@@ -0,0 +1,7 @@
+# Memory management configuration
+mainmenu_option next_comment
+comment 'Memory management configuration'
+
+bool 'Free page cache pages aggressively' CONFIG_FREE_PAGE_CACHE
+
+endmenu
--- linux.orig/arch/i386/config.in Mon May 13 04:17:23 1996
+++ linux/arch/i386/config.in Thu Aug 7 12:13:39 1997
@@ -45,6 +45,8 @@
PPro CONFIG_M686" Pentium
endmenu
+source mm/Config.in
+
source drivers/block/Config.in
if [ "$CONFIG_NET" = "y" ]; then
--- linux.orig/arch/alpha/config.in Mon Aug 5 07:13:50 1996
+++ linux/arch/alpha/config.in Thu Aug 7 12:34:23 1997
@@ -96,6 +96,8 @@
tristate 'Kernel support for ELF binaries' CONFIG_BINFMT_ELF
endmenu
+source mm/Config.in
+
source drivers/block/Config.in
if [ "$CONFIG_NET" = "y" ]; then
--- linux.orig/arch/m68k/config.in Mon May 20 04:54:26 1996
+++ linux/arch/m68k/config.in Thu Aug 7 12:34:21 1997
@@ -33,6 +33,8 @@
fi
endmenu
+source mm/Config.in
+
#
# Block device driver configuration
#
--- linux.orig/arch/mips/config.in Sun May 5 06:05:58 1996
+++ linux/arch/mips/config.in Thu Aug 7 12:34:25 1997
@@ -57,6 +57,8 @@
bool 'Set version information on all symbols for modules' CONFIG_MODVERSIONS
endmenu
+source mm/Config.in
+
source drivers/block/Config.in
if [ "$CONFIG_NET" = "y" ]; then
--- linux.orig/arch/ppc/config.in Mon May 27 09:00:57 1996
+++ linux/arch/ppc/config.in Thu Aug 7 12:34:20 1997
@@ -38,6 +38,8 @@
bool 'Compile kernel as ELF - if your GCC is ELF-GCC' CONFIG_KERNEL_ELF
fi
+source mm/Config.in
+
source drivers/block/Config.in
if [ "$CONFIG_NET" = "y" ]; then
--- linux.orig/arch/sparc/config.in Thu Apr 25 10:22:05 1996
+++ linux/arch/sparc/config.in Thu Aug 7 12:34:24 1997
@@ -31,6 +31,8 @@
tristate 'Kernel support for ELF binaries' CONFIG_BINFMT_ELF
endmenu
+source mm/Config.in
+
mainmenu_option next_comment
comment 'Floppy, IDE, and other block devices'
--- linux.orig/Documentation/Configure.help Tue Aug 5 09:01:41 1997
+++ linux/Documentation/Configure.help Thu Aug 7 12:51:21 1997
@@ -79,6 +79,16 @@
arch/i386/math-emu/README. If you are not sure, say Y; apart from
resulting in a 45kB bigger kernel, it won't hurt.
+Free page cache pages aggressively
+CONFIG_FREE_PAGE_CACHE
+ By default shared page cache and buffer pages are marked as referenced.
+ It makes freeing them very difficult (especially for the page cache).
+ If this option is enabled, shared pages are not marked. Additionally,
+ non referenced pages are aged. It may make low memory machines more
+ usable, as non referenced code pages (which are in most situations
+ the main component of the page cache) are freed aggressively and
+ swapping out of data pages is avoided.
+
Normal floppy disk support
CONFIG_BLK_DEV_FD
If you want to use your floppy disk drive(s) under Linux, say