Home | History | Annotate | Download | only in util 
      1 /*
      2  * Copyright (C) 2011 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.internal.util;
     18 
     19 import android.os.Debug;
     20 import android.os.StrictMode;
     21 
     22 public final class MemInfoReader {
     23     final long[] mInfos = new long[Debug.MEMINFO_COUNT];
     24 
     25     public void readMemInfo() {
     26         // Permit disk reads here, as /proc/meminfo isn't really "on
     27         // disk" and should be fast.  TODO: make BlockGuard ignore
     28         // /proc/ and /sys/ files perhaps?
     29         StrictMode.ThreadPolicy savedPolicy = StrictMode.allowThreadDiskReads();
     30         try {
     31             Debug.getMemInfo(mInfos);
     32         } finally {
     33             StrictMode.setThreadPolicy(savedPolicy);
     34         }
     35     }
     36 
     37     /**
     38      * Total amount of RAM available to the kernel.
     39      */
     40     public long getTotalSize() {
     41         return mInfos[Debug.MEMINFO_TOTAL] * 1024;
     42     }
     43 
     44     /**
     45      * Amount of RAM that is not being used for anything.
     46      */
     47     public long getFreeSize() {
     48         return mInfos[Debug.MEMINFO_FREE] * 1024;
     49     }
     50 
     51     /**
     52      * Amount of RAM that the kernel is being used for caches, not counting caches
     53      * that are mapped in to processes.
     54      */
     55     public long getCachedSize() {
     56         return getCachedSizeKb() * 1024;
     57     }
     58 
     59     /**
     60      * Amount of RAM that is in use by the kernel for actual allocations.
     61      */
     62     public long getKernelUsedSize() {
     63         return getKernelUsedSizeKb() * 1024;
     64     }
     65 
     66     /**
     67      * Total amount of RAM available to the kernel.
     68      */
     69     public long getTotalSizeKb() {
     70         return mInfos[Debug.MEMINFO_TOTAL];
     71     }
     72 
     73     /**
     74      * Amount of RAM that is not being used for anything.
     75      */
     76     public long getFreeSizeKb() {
     77         return mInfos[Debug.MEMINFO_FREE];
     78     }
     79 
     80     /**
     81      * Amount of RAM that the kernel is being used for caches, not counting caches
     82      * that are mapped in to processes.
     83      */
     84     public long getCachedSizeKb() {
     85         return mInfos[Debug.MEMINFO_BUFFERS]
     86                 + mInfos[Debug.MEMINFO_CACHED] - mInfos[Debug.MEMINFO_MAPPED];
     87     }
     88 
     89     /**
     90      * Amount of RAM that is in use by the kernel for actual allocations.
     91      */
     92     public long getKernelUsedSizeKb() {
     93         return mInfos[Debug.MEMINFO_SHMEM] + mInfos[Debug.MEMINFO_SLAB]
     94                 + mInfos[Debug.MEMINFO_VM_ALLOC_USED] + mInfos[Debug.MEMINFO_PAGE_TABLES]
     95                 + mInfos[Debug.MEMINFO_KERNEL_STACK];
     96     }
     97 
     98     public long getSwapTotalSizeKb() {
     99         return mInfos[Debug.MEMINFO_SWAP_TOTAL];
    100     }
    101 
    102     public long getSwapFreeSizeKb() {
    103         return mInfos[Debug.MEMINFO_SWAP_FREE];
    104     }
    105 
    106     public long getZramTotalSizeKb() {
    107         return mInfos[Debug.MEMINFO_ZRAM_TOTAL];
    108     }
    109 
    110     public long[] getRawInfo() {
    111         return mInfos;
    112     }
    113 }
    114