#Raise photo and video recording quality
#Raise JPG quality to 100%
#Enables register map for tracking objects to garbage collect. Might give a little more RAM at the cost of a few CPU cycles.
#Raise photo and video recording quality
#Enable surface dithering
#Allow purging of assets
#Force launcher into memory
# Disables data sent and logging.Only for HTC
#sleep mode for battery savings. 0 power collapse suspend, 1 power collapse (best), 2 apps go to sleep, 3 show clock and wait, 4 wait for interrupt
#Fix some application issues/Disable kernel error logging
flash this zip
VSync synchronizes things. It tells the GPU to wait for the screen to finish its line by line drawing before loading the next frame.
The VSync pulse is now used to start all the processing for the next frame.
flash this zip
xperia 2011 devices only
collection of newest xperia libs
xperia T jelly bean libs, xperia S modified adreno libs, new egl libs, xperia V/T sound libs
Copy it on your sd card
move to right place
This enables block I/O debugging when set to a nonzero value. If you want to find out which process caused the disk to spin up (see /proc/sys/vm/laptop_mode), you can gather information by setting the flag.
When this flag is set, Linux reports all disk read and write operations that take place, and all block dirtyings done to files. This makes it possible to debug why a disk needs to spin up, and to increase battery life even more. The output of block_dump is written to the kernel output, and it can be retrieved using "dmesg". When you use block_dump and your kernel logging level also includes kernel debugging messages, you probably want to turn off klogd, otherwise the output of block_dump will be logged, causing disk activity that is not normally there.
Contains the amount of dirty memory at which the pdflush background writeback daemon will start writeback.
If dirty_background_bytes is written, dirty_background_ratio becomes a function of its value (dirty_background_bytes / the amount of dirtyable system memory).
Contains, as a percentage of total system memory, the number of pages at which the pdflush background writeback daemon will start writing out dirty data.
Contains the amount of dirty memory at which a process generating disk writes will itself start writeback.
If dirty_bytes is written, dirty_ratio becomes a function of its value (dirty_bytes / the amount of dirtyable system memory).
Note: the minimum value allowed for dirty_bytes is two pages (in bytes); any value lower than this limit will be ignored and the old configuration will be retained.
vm/dirty_expire_centisecs and vm/dirty_writeback_centisecs
How old "dirty" data should be before the kernel considers it old enough to be written to disk. It is expressed in 100ths of a second.
This is the interval of when the writeback daemons periodically wake up and write "old" data out to disk. It is expressed in 100ths of a second.
Contains, as a percentage of total system memory, the number of pages at which a process which is generating disk writes will itself start writing out dirty data.
Writing to this will cause the kernel to drop clean caches, dentries and inodes from memory, causing that memory to become free.
To free pagecache:
echo 1 > /proc/sys/vm/drop_caches
To free dentries and inodes:
echo 2 > /proc/sys/vm/drop_caches
To free pagecache, dentries and inodes:
echo 3 > /proc/sys/vm/drop_caches
As this is a non-destructive operation, and dirty objects are not freeable, the user should run "sync" first in order to make sure all cached objects are freed.
laptop_mode is a knob that controls "laptop mode". When the knob is set, any physical disk I/O (that might have caused the hard disk to spin up, see /proc/sys/vm/block_dump) causes Linux to flush all dirty blocks. The result of this is that after a disk has spun down, it will not be spun up anymore to write dirty blocks, because those blocks had already been written immediately after the most recent read operation. The value of the laptop_mode knob determines the time between the occurrence of disk I/O and when the flush is triggered. A sensible value for the knob is 5 seconds. Setting the knob to 0 disables laptop mode.
Ratio of total pages to free pages for each memory zone.
This file contains the maximum number of memory map areas a process may have. Memory map areas are used as a side-effect of calling malloc, directly by mmap and mprotect, and also when loading shared libraries.
While most applications need less than a thousand maps, certain programs, particularly malloc debuggers, may consume lots of them, e.g., up to one or two maps per allocation.
The default value is 65536.
This is used to force the Linux VM to keep a minimum number of kilobytes free. The VM uses this number to compute a pages_min value for each lowmem zone in the system. Each lowmem zone gets a number of reserved free pages based proportionally on its size.
This file indicates the amount of address space which a user process will be restricted from mmaping. Since kernel null dereference bugs could accidentally operate based on the information in the first couple of pages of memory userspace processes should not be allowed to write to them.
By default this value is set to 0 and no protections will be enforced by the security module. Setting this value to something like 64k will allow the vast majority of applications to work correctly and provide defense in depth against future potential kernel bugs.
The count of currently-running pdflush threads. This is a read-only value.
Enables a system-wide task dump (excluding kernel threads) to be produced when the kernel performs an OOM-killing and includes such information as pid, uid, tgid, vm size, rss, cpu, oom_adj score, and name. This is helpful to determine why the OOM killer was invoked and to identify the rogue task that caused it.
If this is set to zero, this information is suppressed. On very large systems with thousands of tasks it may not be feasible to dump the memory state information for each one. Such systems should not be forced to incur a performance penalty in OOM conditions when the information may not be desired.
If this is set to non-zero, this information is shown whenever the OOM killer actually kills a memory-hogging task.
The default value is 0.
This enables or disables killing the OOM-triggering task in out-of-memory situations.
If this is set to zero, the OOM killer will scan through the entire tasklist and select a task based on heuristics to kill. This normally selects a rogue memory-hogging task that frees up a large amount of memory when killed.
If this is set to non-zero, the OOM killer simply kills the task that triggered the out-of-memory condition. This avoids the expensive tasklist scan.
If panic_on_oom is selected, it takes precedence over whatever value is used in oom_kill_allocating_task.
The default value is 0.
vm overcommit memory
This controls overcommit of system memory, possibly allowing processes to allocate (but not use) more memory than is actually available.
0 - Heuristic overcommit handling. Obvious overcommits of address space are refused. Used for a typical system. It ensures a seriously wild allocation fails while allowing overcommit to reduce swap usage. root is allowed to allocate slighly more memory in this mode. This is the default.
1 - Always overcommit. Appropriate for some scientific applications.
2 - Don't overcommit. The total address space commit for the system is not permitted to exceed swap plus a configurable percentage (default is 50) of physical RAM. Depending on the percentage you use, in most situations this means a process will not be killed while attempting to use already-allocated memory but will receive errors on memory allocation as appropriate.
vm overcommit ratio
Percentage of physical memory size to include in overcommit calculations.
Memory allocation limit = swapspace + physmem * (overcommit_ratio / 100)
swapspace = total size of all swap areas
physmem = size of physical memory in system
This controls the number of pages which are written to swap in a single attempt. The swap I/O size.
It is a logarithmic value - setting it to zero means "1 page", setting it to 1 means "2 pages", setting it to 2 means "4 pages", etc.
The default value is three (eight pages at a time). There may be some small benefits in tuning this to a different value if your workload is swap-intensive.
This enables or disables panic on out-of-memory feature. If this is set to 1, the kernel panics when out-of-memory happens. If this is set to 0, the kernel will kill some rogue process, by calling oom_kill().
Usually, oom_killer can kill rogue processes and system will survive. If you want to panic the system rather than killing rogue processes, set this to 1.
The default value is 0.
Panic is a system error that is detected by the kernel.
This is the fraction of pages at most (high mark pcp->high) in each zone that are allocated for each per cpu page list. The min value for this is 8. It means that we don't allow more than 1/8th of pages in each zone to be allocated in any single per_cpu_pagelist. This entry only changes the value of hot per cpu pagelists. User can specify a number like 100 to allocate 1/100th of each zone to each per cpu page list.
The batch value of each per cpu pagelist is also updated as a result. It is set to pcp->high / 4. The upper limit of batch is (PAGE_SHIFT * 8).
The initial value is zero. Kernel does not use this value at boot time to set the high water marks for each per cpu page list.
When written to, this tunable will initiate a scan of individual or all zones' unevictable lists and move any pages that have become evictable onto the respective zone's inactive list, where shrink_inactive_list() will deal with them. If evictable pages are found in unevictable lru, kernel will print filenames and file offsets of those pages.
swappiness is a parameter which sets the kernel's balance between reclaiming pages from the page cache and swapping process memory. The default value is 60.
If you want kernel to swap out more process memory and thus cache more file contents increase the value. Otherwise, if you would like kernel to swap less decrease it. more information
vm vfs cache presure
Now here is where it gets interesting! File system cache (dentry/inode) is really more important than the block cache above in dirty ratio and dirty background ratio, so we really want the kernel to use up much more of the RAM for file system cache, this will increas the performance of the system without sacrificing performance at the application level. The default value is 100, as a percentage, and what you want to do is lower the value to tell the kernel to favor the file system cache and not drop them aggressively.
Over the years, since evenbefore Android entered the scene, we have striven to … more
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