TODO: DRAM test

Referece:
     https://github.com/littlekernel/lk/tree/master/app
     memtest


Source http://benjr.tw/96460

Linux command – Memtester

2017-01-17 adminLinux, Memory, Ubuntu

 701 total views, 2 views today

之前用過 Memtest86+ http://benjr.tw/491 ,無法直接在 Linux 環境下直接來使用,Memtester 可以直接在 Linux 環境下執行,且可以從 apt-get 下載使用,官方網站 http://pyropus.ca/software/memtester/

root@ubuntu:~# apt-get install memtester Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   linux-headers-4.4.0-31 linux-headers-4.4.0-31-generic   linux-image-4.4.0-31-generic linux-image-extra-4.4.0-31-generic Use 'apt autoremove' to remove them. The following NEW packages will be installed:   memtester 0 upgraded, 1 newly installed, 0 to remove and 8 not upgraded. Need to get 16.2 kB of archives. After this operation, 66.6 kB of additional disk space will be used. Get:1 http://us.archive.ubuntu.com/ubuntu xenial/universe amd64 memtester amd64 4.3.0-3 [16.2 kB] Fetched 16.2 kB in 1s (11.6 kB/s)                      Selecting previously unselected package memtester. (Reading database ... 242316 files and directories currently installed.) Preparing to unpack .../memtester_4.3.0-3_amd64.deb ... Unpacking memtester (4.3.0-3) ... Processing triggers for man-db (2.7.5-1) ... Setting up memtester (4.3.0-3) ...

使用上也很簡單,只需要指定要測試的記憶體大小 (單位: B/K/M/G) 以及測試次數 (Loops) 即可.

Usage: memtester [-p physaddrbase [-d device]] [B|K|M|G] [loops]

我的系統是 Ubuntu16.04 1G 記憶體 的 VMware 虛擬機器.

root@ubuntu:~# memtester 200M 1 memtester version 4.3.0 (64-bit) Copyright (C) 2001-2012 Charles Cazabon. Licensed under the GNU General Public License version 2 (only).   pagesize is 4096 pagesizemask is 0xfffffffffffff000 want 200MB (209715200 bytes) got  200MB (209715200 bytes), trying mlock ...locked. Loop 1/1:   Stuck Address       : ok           Random Value        : ok   Compare XOR         : ok   Compare SUB         : ok   Compare MUL         : ok   Compare DIV         : ok   Compare OR          : ok   Compare AND         : ok   Sequential Increment: ok   Solid Bits          : ok           Block Sequential    : ok           Checkerboard        : ok           Bit Spread          : ok           Bit Flip            : ok           Walking Ones        : ok           Walking Zeroes      : ok           8-bit Writes        : ok   16-bit Writes       : ok   Done.

Memtester 主要會針對記憶體做以下的測試

1. Stuck Address
2. Random Value -test random value
3. Compare XOR – test xor comparison
4. Compare SUB – test sub comparison
5. Compare MUL – test mul comparison
6. Compare DIV – test div comparison
7. Compare OR – test or comparison
8. Compare AND – test and comparison
9. Sequential Increment – test seqinc comparison
10. Solid Bits – test solidbits comparison
11. Block Sequential – test blockseq comparison
12. Checkerboard – test checkerboard comparison
13. Bit Spread – test bitspread comparison
14. Bit Flip – test bitflip comparison
15. Walking Ones – test walk bits 1 comparison
16. Walking Zeroes – test_walk bits 0 comparison
17. 8-bit Writes – test 8bit wide random
18. 16-bit Writes -test 16bit wide random

memtester 是透過 malloc 函數來要求記憶體空間,所以在設定測試記憶體空間時沒有辦法把全部的記憶體都拿來測試.

root@ubuntu:~# free               total        used        free      shared  buff/cache   available Mem:         998312      158264      740632          80       99416      698696 Swap:       1046524      492832      553692

透過 free 可以看到,系統大概還有 700M 可以用,所以上限大概也就在這裡.
Linux 底下記憶體的使用區分下面幾種.

• Total Memory 
  系統所有的記憶體容量.
• Used Memory
  Total(998,312) – Free(740632) – Buffers/Cache(99416) 就是目前所有有在使用中的記憶體數量.
• Free Memory
  尚未使用到的的記憶體.
• shared Memory
  used by tmpfs , 允許 processes (程序) 透過 Shared memory 共享儲存於記憶體中的 common structures 和 Data.
• Buffered Memory
  資料還來不及儲存到硬碟中暫儲在記憶體的資料.
• Cached Memory
  資料已經由硬碟中讀取出來,提供給應用程式接下來使用,用以提高存取效能.
• Available
  估計有多少記憶體可用於啟動新應用程式,無需透過 swapping

超過系統能給的時候 memtester 就不會繼續執行.

root@ubuntu:~# memtester 1G 1 memtester version 4.3.0 (64-bit) Copyright (C) 2001-2012 Charles Cazabon. Licensed under the GNU General Public License version 2 (only).   pagesize is 4096 pagesizemask is 0xfffffffffffff000 want 1024MB (1073741824 bytes) got  1024MB (1073741824 bytes), trying mlock ...Killed

root@ubuntu:~# memtester 700M 1 memtester version 4.3.0 (64-bit) Copyright (C) 2001-2012 Charles Cazabon. Licensed under the GNU General Public License version 2 (only).   pagesize is 4096 pagesizemask is 0xfffffffffffff000 want 700MB (734003200 bytes) got  700MB (734003200 bytes), trying mlock ...locked. Loop 1/1:   Stuck Address       : ok           Random Value        : ok   Compare XOR         : ok   Compare SUB         : ok   Compare MUL         : ok   Compare DIV         : ok   Compare OR          : ok   Compare AND         : ok   Sequential Increment: ok   Solid Bits          : ok           Block Sequential    : ok           Checkerboard        : ok           Bit Spread          : ok           Bit Flip            : setting  99Killed