ROM優化技巧

Init.d (system/etc/Init.d 一般民間rom都有該目錄, 木有的話自己創建)

(需要 ROM 有/system/etc/init.d 目錄, 並且需要busybox能正常使用. 創建一個空白文件,每個文件第一行都需要有 ?> #!/system/bin/sh , 拖拽進 /system/etc/init.d 然後命名類似77tweaks *( 數字,然後名稱)

1. strict minfree handler 優化

參數:

echo “2048,3072,6144,15360,17920,20480″ > /sys/module/lowmemorykiller/parameters/minfree

2. 網絡速度優化

參數:

echo “0″ > /proc/sys/net/ipv4/tcp_timestamps;

echo “1″ > /proc/sys/net/ipv4/tcp_tw_reuse;

echo “1″ > /proc/sys/net/ipv4/tcp_sack;

echo “1″ > /proc/sys/net/ipv4/tcp_tw_recycle;

echo “1″ > /proc/sys/net/ipv4/tcp_window_scaling;

echo “5″ > /proc/sys/net/ipv4/tcp_keepalive_probes;

echo “30″ > /proc/sys/net/ipv4/tcp_keepalive_intvl;

echo “30″ > /proc/sys/net/ipv4/tcp_fin_timeout;

echo “404480″ > /proc/sys/net/core/wmem_max;

echo “404480″ > /proc/sys/net/core/rmem_max;

echo “256960″ > /proc/sys/net/core/rmem_default;

echo “256960″ > /proc/sys/net/core/wmem_default;

echo “4096,16384,404480″ > /proc/sys/net/ipv4/tcp_wmem;

echo “4096,87380,404480″ > /proc/sys/net/ipv4/tcp_rmem;

3. vm 虛擬機管理優化

參數:

echo “4096″ > /proc/sys/vm/min_free_kbytes

echo “0″ > /proc/sys/vm/oom_kill_allocating_task;

echo “0″ > /proc/sys/vm/panic_on_oom;

echo “0″ > /proc/sys/vm/laptop_mode;

echo “0″ > /proc/sys/vm/swappiness

echo “50″ > /proc/sys/vm/vfs_cache_pressure

echo “90″ > /proc/sys/vm/dirty_ratio

echo “70″ > /proc/sys/vm/dirty_background_ratio

4. 內核優化

參數:

echo “8″ > /proc/sys/vm/page-cluster;

echo “64000″ > /proc/sys/kernel/msgmni;

echo “64000″ > /proc/sys/kernel/msgmax;

echo “10″ > /proc/sys/fs/lease-break-time;

echo “500,512000,64,2048″ > /proc/sys/kernel/sem;

5. 電池優化

參數:

echo “500″ > /proc/sys/vm/dirty_expire_centisecs

echo “1000″ > /proc/sys/vm/dirty_writeback_centisecs

6. EXT4 優化 (增加 I/O 調度)(需要 /system, /cache, /data 格式化分區為 EXT4))

a)移除 journalism

參數:

tune2fs -o journal_data_writeback /block/path/to/system

tune2fs -O ^has_journal /block/path/to/system

tune2fs -o journal_data_writeback /block/path/to/cache

tune2fs -O ^has_journal /block/path/to/cache

tune2fs -o journal_data_writeback /block/path/to/data

tune2fs -O ^has_journal /block/path/to/data

b) 完美掛載選項

參數:

busybox mount -o remount,noatime,noauto_da_alloc,nosuid,nodev,nodiratime,barrier=0,nobh /system

busybox mount -o remount,noatime,noauto_da_alloc,nosuid,nodev,nodiratime,barrier=0,nobh /data

busybox mount -o remount,noatime,noauto_da_alloc,nosuid,nodev,nodiratime,barrier=0,nobh /cache

7.標識區為不可自旋轉並增加緩存大小

參數:

LOOP=`ls -d /sys/block/loop*`;

RAM=`ls -d /sys/block/ram*`;

MMC=`ls -d /sys/block/mmc*`;

for j in $LOOP $RAM

do

echo “0″ > $j/queue/rotational;

echo “2048″ > $j/queue/read_ahead_kb;

done

8. SD 卡速度優化

參數:

echo “2048″ > /sys/devices/virtual/bdi/179:0/read_ahead_kb;

9. Defrags database files

參數:

for i in

`find /data -iname “*.db”`

do

sqlite3 $i ‘VACUUM;’;

done

9. 移除 logger

參數:

rm /dev/log/main

10. Ondemand governor (超頻優化)

參數:

SAMPLING_RATE=$(busybox expr `cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_transition_latency`

* 750 / 1000)

echo 95 > /sys/devices/system/cpu/cpufreq/ondemand/up_threshold

echo $SAMPLING_RATE > /sys/devices/system/cpu/cpu0/cpufreq/ondemand/sampling_rate

自動更改governor 與 I/O 調度

a) I/O 調度 (最佳: MTD 設備 ? VR; EMMC 設備 ? SIO) ? 需要適應的內核