内存耗用：VSS/RSS/PSS/USS_sprd

异常信息有:

------ PROCRANK (procrank) ------

PID Vss Rss Pss Uss cmdline

2540 55172K 52076K 32177K 30596K com.xxx.yyy

1259 65212K 48196K 26297K 23476K system_server

1601 39740K 38220K 19066K 17492K com.android.settings

1363 32636K 32624K 13923K 12788K com.android.phone

5663 31356K 31336K 12313K 10916K com.estrongs.android.pop

5740 31464K 31448K 11851K 10168K com.android.launcher

1510 25188K 25152K 9039K 8180K android.process.media

1651 27600K 27584K 8733K 7572K com.android.deskclock

1369 29400K 26536K 8165K 6904K com.android.systemui

3340 26816K 26784K 8068K 6768K com.wd.AndroidDaemon

3004 26324K 26304K 8031K 6624K com.cooliris.media

3870 25648K 25612K 8019K 6836K com.tencent.qqpimsecure

4872 21516K 21476K 6224K 5268K com.google.android.apps.maps

1423 22528K 22508K 5948K 5056K com.android.inputmethod.pinyin

5796 23056K 23028K 5741K 4548K com.android.mms

5217 21680K 21628K 5458K 4560K android.process.acore

4165 21052K 21004K 5301K 4368K com.qihoo360.mobilesafe

1756 21768K 21744K 4776K 3852K com.android.quicksearchbox

1080 25020K 24956K 4010K 1696K zygote

3449 19116K 19064K 3752K 2868K com.wd.AndroidDaemon:service

1367 19040K 18996K 3264K 2468K cn.cbc.cmmb.sdk

1068 4900K 4836K 2702K 2148K /system/bin/mediaserver

1362 17472K 17424K 2570K 1820K com.yeezonetech.firewall

5861 16156K 16112K 2216K 1424K com.android.defcontainer

1584 1020K 1016K 772K 764K logcat

6014 772K 764K 555K 552K procrank

1044 1588K 1584K 451K 312K /system/bin/engpcclient

3898 668K 664K 416K 408K logcat

1086 1068K 1064K 344K 228K /system/bin/synergy_service

1147 584K 580K 332K 328K /system/bin/phoneserver

1079 888K 888K 318K 296K /system/bin/rild_sp

1039 268K 268K 248K 248K /sbin/adbd

2935 456K 452K 236K 232K /data/xmesg

1076 620K 616K 228K 192K /system/bin/vold

1 264K 264K 196K 156K /init

1077 572K 568K 194K 160K /system/bin/netd

1093 656K 652K 191K 176K /system/bin/cmmbserver

1577 720K 716K 178K 156K vhub

1040 700K 692K 176K 156K /system/bin/nvitemd

1579 708K 704K 173K 152K vhub

1574 700K 696K 169K 148K vhub

1565 700K 692K 165K 144K vhub1

6012 428K 424K 149K 144K /system/bin/dumpstate

1083 428K 420K 111K 96K /system/bin/dbus-daemon

1084 364K 360K 108K 104K /system/bin/installd

639 148K 148K 108K 68K /sbin/ueventd

6010 352K 344K 107K 76K /system/bin/sh

1085 432K 424K 106K 80K /system/bin/keystore

1583 352K 348K 104K 96K logcat

1232 368K 360K 103K 96K hciattach

1046 344K 340K 96K 92K /system/bin/engmodemclient

1038 324K 316K 95K 64K /system/bin/sh

1094 216K 216K 94K 52K /system/xbin/busybox

1091 216K 216K 94K 52K /system/xbin/busybox

1097 208K 208K 88K 48K /system/xbin/busybox

1092 428K 420K 88K 80K /system/bin/akmd8975

1231 304K 296K 87K 84K csrbluezcoexsniffer

1582 200K 200K 86K 48K /system/xbin/busybox

6011 324K 316K 84K 80K bugreport

1045 312K 308K 84K 80K /system/bin/engservice

1043 312K 308K 80K 76K /system/bin/modemd

1067 288K 280K 79K 76K /system/bin/servicemanager

1047 300K 292K 75K 72K /system/bin/vcharged

1089 296K 288K 71K 64K /system/bin/logwrapper

1090 296K 288K 71K 64K /system/bin/logwrapper

1042 284K 276K 63K 60K /system/bin/sprd_monitor

1060 276K 268K 63K 60K open_ttyNK

1078 256K 248K 55K 52K /system/bin/debuggerd

[procrank: 0.8s elapsed]

经查阅：

VSS- Virtual Set Size 虚拟耗用内存（包含共享库占用的内存）RSS- Resident Set Size 实际使用物理内存（包含共享库占用的内存）PSS- Proportional Set Size 实际使用的物理内存（比例分配共享库占用的内存）USS- Unique Set Size 进程独自占用的物理内存（不包含共享库占用的内存）

一般来说内存占用大小有如下规律：VSS >= RSS >= PSS >= USS

Overview

The aim of this post is to provide information that will assist in interpreting memory reports from various tools so the true memory usage for Linux processes and the system can be determined.

Android has a tool calledprocrank(/system/xbin/procrank), which lists out the memory usage of Linux processes in order from highest to lowest usage. The sizes reported per process are VSS, RSS, PSS, and USS.

For the sake of simplicity in this description, memory will be expressed in terms of pages, rather than bytes. Linux systems like ours manage memory in 4096 byte pages at the lowest level.

VSS(reported as VSZ from ps) isthe total accessible address space of a process.This size also includes memory that may not be resident in RAM like mallocs that have been allocated but not written to. VSS is of very little use for determing real memory usage of a process.

RSSis thetotal memory actually held in RAM for a process.RSS can be misleading, because it reports the total all of the shared libraries that the process uses, even though a shared library is only loaded into memory once regardless of how many processes use it. RSS is not an accurate representation of the memory usage for a single process.

PSSdiffers from RSS in that it reports the proportional size of its shared libraries, i.e. if three processes all use a shared library that has 30 pages, that library will only contribute 10 pages to the PSS that is reported for each of the three processes. PSS is a very useful number because when the PSS for all processes in the system are summed together, that is a good representation for the total memory usage in the system. When a process is killed, the shared libraries that contributed to its PSS will be proportionally distributed to the PSS totals for the remaining processes still using that library. In this way PSS can be slightly misleading, because when a process is killed, PSS does not accurately represent the memory returned to the overall system.

USSisthe total private memory for a process, i.e. that memory that is completely unique to that process.USS is an extremely useful number because it indicates the true incremental cost of running a particular process. When a process is killed, the USS is the total memory that is actually returned to the system. USS is the best number to watch when initially suspicious ofmemory leaksin a process.

For systems that have Python available, there is also a nice tool calledsmemthat will report memory statistics including all of these categories.