ZONE_DMA, 4 chunks of 2^1*PAGE_SIZE in ZONE_DMA, 101 chunks of 2^4*PAGE_SIZE
available in ZONE_NORMAL, etc...
+
+1.3 IDE devices in /proc/ide
+----------------------------
+
+The subdirectory /proc/ide contains information about all IDE devices of which
+the kernel is aware. There is one subdirectory for each IDE controller, the
+file drivers and a link for each IDE device, pointing to the device directory
+in the controller specific subtree.
+
+The file drivers contains general information about the drivers used for the
+IDE devices:
+
+ > cat /proc/ide/drivers
+ ide-cdrom version 4.53
+ ide-disk version 1.08
+
..............................................................................
meminfo:
Writeback: 0 kB
Mapped: 280372 kB
Slab: 684068 kB
-CommitLimit: 7669796 kB
-Committed_AS: 100056 kB
+Committed_AS: 1576424 kB
PageTables: 24448 kB
+ReverseMaps: 1080904
VmallocTotal: 112216 kB
VmallocUsed: 428 kB
VmallocChunk: 111088 kB
Writeback: Memory which is actively being written back to the disk
Mapped: files which have been mmaped, such as libraries
Slab: in-kernel data structures cache
- CommitLimit: Based on the overcommit ratio ('vm.overcommit_ratio'),
- this is the total amount of memory currently available to
- be allocated on the system. This limit is only adhered to
- if strict overcommit accounting is enabled (mode 2 in
- 'vm.overcommit_memory').
- The CommitLimit is calculated with the following formula:
- CommitLimit = ('vm.overcommit_ratio' * Physical RAM) + Swap
- For example, on a system with 1G of physical RAM and 7G
- of swap with a `vm.overcommit_ratio` of 30 it would
- yield a CommitLimit of 7.3G.
- For more details, see the memory overcommit documentation
- in vm/overcommit-accounting.
-Committed_AS: The amount of memory presently allocated on the system.
- The committed memory is a sum of all of the memory which
- has been allocated by processes, even if it has not been
- "used" by them as of yet. A process which malloc()'s 1G
- of memory, but only touches 300M of it will only show up
- as using 300M of memory even if it has the address space
- allocated for the entire 1G. This 1G is memory which has
- been "committed" to by the VM and can be used at any time
- by the allocating application. With strict overcommit
- enabled on the system (mode 2 in 'vm.overcommit_memory'),
- allocations which would exceed the CommitLimit (detailed
- above) will not be permitted. This is useful if one needs
- to guarantee that processes will not fail due to lack of
- memory once that memory has been successfully allocated.
+Committed_AS: An estimate of how much RAM you would need to make a
+ 99.99% guarantee that there never is OOM (out of memory)
+ for this workload. Normally the kernel will overcommit
+ memory. That means, say you do a 1GB malloc, nothing
+ happens, really. Only when you start USING that malloc
+ memory you will get real memory on demand, and just as
+ much as you use. So you sort of take a mortgage and hope
+ the bank doesn't go bust. Other cases might include when
+ you mmap a file that's shared only when you write to it
+ and you get a private copy of that data. While it normally
+ is shared between processes. The Committed_AS is a
+ guesstimate of how much RAM/swap you would need
+ worst-case.
PageTables: amount of memory dedicated to the lowest level of page
tables.
+ ReverseMaps: number of reverse mappings performed
VmallocTotal: total size of vmalloc memory area
VmallocUsed: amount of vmalloc area which is used
VmallocChunk: largest contigious block of vmalloc area which is free
-
-1.3 IDE devices in /proc/ide
-----------------------------
-
-The subdirectory /proc/ide contains information about all IDE devices of which
-the kernel is aware. There is one subdirectory for each IDE controller, the
-file drivers and a link for each IDE device, pointing to the device directory
-in the controller specific subtree.
-
-The file drivers contains general information about the drivers used for the
-IDE devices:
-
- > cat /proc/ide/drivers
- ide-cdrom version 4.53
- ide-disk version 1.08
-
More detailed information can be found in the controller specific
subdirectories. These are named ide0, ide1 and so on. Each of these
directories contains the files shown in table 1-4.
block_dump enables block I/O debugging when set to a nonzero value. More
information on block I/O debugging is in Documentation/laptop-mode.txt.
-swap_token_timeout
-------------------
-
-This file contains valid hold time of swap out protection token. The Linux
-VM has token based thrashing control mechanism and uses the token to prevent
-unnecessary page faults in thrashing situation. The unit of the value is
-second. The value would be useful to tune thrashing behavior.
-
2.5 /proc/sys/dev - Device specific parameters
----------------------------------------------
git://git.onelab.eu / linux-2.6.git / blobdiff