kernel/linux.git/include/linux/vmstat.h, branch linux-2.6.22.y

vmstat: use our own timer events

2007-05-09T19:30:56+00:00

vmstat is currently using the cache reaper to periodically bring the statistics up to date. The cache reaper does only exists in SLUB as a way to provide compatibility with SLAB. This patch removes the vmstat calls from the slab allocators and provides its own handling. The advantage is also that we can use a different frequency for the updates. Refreshing vm stats is a pretty fast job so we can run this every second and stagger this by only one tick. This will lead to some overlap in large systems. F.e a system running at 250 HZ with 1024 processors will have 4 vm updates occurring at once. However, the vm stats update only accesses per node information. It is only necessary to stagger the vm statistics updates per processor in each node. Vm counter updates occurring on distant nodes will not cause cacheline contention. We could implement an alternate approach that runs the first processor on each node at the second and then each of the other processor on a node on a subsequent tick. That may be useful to keep a large amount of the second free of timer activity. Maybe the timer folks will have some feedback on this one? [jirislaby@gmail.com: add missing break] Cc: Arjan van de Ven Signed-off-by: Christoph Lameter Signed-off-by: Jiri Slaby Cc: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] count_vm_events-warning-fix

2007-02-11T18:51:25+00:00

- Prevent things like this: block/ll_rw_blk.c: In function 'submit_bio': block/ll_rw_blk.c:3222: warning: unused variable 'count' inlines are very, very preferable to macros. - remove unused get_cpu_vm_events() macro Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] optional ZONE_DMA: optional ZONE_DMA in the VM

2007-02-11T18:51:18+00:00

Make ZONE_DMA optional in core code. - ifdef all code for ZONE_DMA and related definitions following the example for ZONE_DMA32 and ZONE_HIGHMEM. - Without ZONE_DMA, ZONE_HIGHMEM and ZONE_DMA32 we get to a ZONES_SHIFT of 0. - Modify the VM statistics to work correctly without a DMA zone. - Modify slab to not create DMA slabs if there is no ZONE_DMA. [akpm@osdl.org: cleanup] [jdike@addtoit.com: build fix] [apw@shadowen.org: Simplify calculation of the number of bits we need for ZONES_SHIFT] Signed-off-by: Christoph Lameter Cc: Andi Kleen Cc: "Luck, Tony" Cc: Kyle McMartin Cc: Matthew Wilcox Cc: James Bottomley Cc: Paul Mundt Signed-off-by: Andy Whitcroft Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Drop free_pages()

2007-02-11T18:51:18+00:00

nr_free_pages is now a simple access to a global variable. Make it a macro instead of a function. The nr_free_pages now requires vmstat.h to be included. There is one occurrence in power management where we need to add the include. Directly refrer to global_page_state() there to clarify why the #include was added. [akpm@osdl.org: arm build fix] [akpm@osdl.org: sparc64 build fix] Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Use ZVC for inactive and active counts

2007-02-11T18:51:17+00:00

The determination of the dirty ratio to determine writeback behavior is currently based on the number of total pages on the system. However, not all pages in the system may be dirtied. Thus the ratio is always too low and can never reach 100%. The ratio may be particularly skewed if large hugepage allocations, slab allocations or device driver buffers make large sections of memory not available anymore. In that case we may get into a situation in which f.e. the background writeback ratio of 40% cannot be reached anymore which leads to undesired writeback behavior. This patchset fixes that issue by determining the ratio based on the actual pages that may potentially be dirty. These are the pages on the active and the inactive list plus free pages. The problem with those counts has so far been that it is expensive to calculate these because counts from multiple nodes and multiple zones will have to be summed up. This patchset makes these counters ZVC counters. This means that a current sum per zone, per node and for the whole system is always available via global variables and not expensive anymore to calculate. The patchset results in some other good side effects: - Removal of the various functions that sum up free, active and inactive page counts - Cleanup of the functions that display information via the proc filesystem. This patch: The use of a ZVC for nr_inactive and nr_active allows a simplification of some counter operations. More ZVC functionality is used for sums etc in the following patches. [akpm@osdl.org: UP build fix] Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] fix vm_events_fold_cpu() build breakage

2006-12-22T16:55:48+00:00

fix vm_events_fold_cpu() build breakage 2.6.20-rc1 does not build properly if CONFIG_VM_EVENT_COUNTERS is set and CONFIG_HOTPLUG is unset: CC init/version.o LD init/built-in.o LD .tmp_vmlinux1 mm/built-in.o: In function `page_alloc_cpu_notify': page_alloc.c:(.text+0x56eb): undefined reference to `vm_events_fold_cpu' make: *** [.tmp_vmlinux1] Error 1 [akpm@osdl.org: cleanup] Signed-off-by: Magnus Damm Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] CONFIG_VM_EVENT_COUNTER comment decrustify

2006-12-22T16:55:46+00:00

The VM event counters, enabled by CONFIG_VM_EVENT_COUNTERS, which provides VM event counters in /proc/vmstat, has become more essential to non-EMBEDDED kernel configurations than they were in the past. Comments in the code and the Kconfig configuration explanation were stale, downplaying their role excessively. Refresh those comments to correctly reflect the current role of VM event counters. Signed-off-by: Paul Jackson Acked-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Remove another config.h

2006-09-29T16:18:13+00:00

After the asm/ uses of #include this one is the next biggest source of noise. Signed-off-by: Dave Jones Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] reduce MAX_NR_ZONES: remove display of counters for unconfigured zones

2006-09-26T15:48:47+00:00

eventcounters: Do not display counters for zones that are not available on an arch Do not define or display counters for the DMA32 and the HIGHMEM zone if such zones were not configured. [akpm@osdl.org: s390 fix] [heiko.carstens@de.ibm.com: s390 fix] Signed-off-by: Christoph Lameter Cc: Martin Schwidefsky Signed-off-by: Heiko Carstens Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] reduce MAX_NR_ZONES: make ZONE_DMA32 optional

2006-09-26T15:48:46+00:00

Make ZONE_DMA32 optional - Add #ifdefs around ZONE_DMA32 specific code and definitions. - Add CONFIG_ZONE_DMA32 config option and use that for x86_64 that alone needs this zone. - Remove the use of CONFIG_DMA_IS_DMA32 and CONFIG_DMA_IS_NORMAL for ia64 and fix up the way per node ZVCs are calculated. - Fall back to prior GFP_ZONEMASK of 0x03 if there is no DMA32 zone. Signed-off-by: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds