How should I read these figures from top? Where's the memory gone?

Question

I'm looking at these figures in top:

Mem:   3891192k total,  3659276k used,   231916k free,    25640k buffers
Swap:  4449924k total,        0k used,  4449924k free,  1237416k cached

and struggling to see where all the 3659276k has gone. The top processes sorted by memory look like:

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
30228 myuser    25   0 2914m 2.2g 9908 S 13.3 59.6   4:59.05 java
26428 root      25   0 97580  17m 8024 S  0.7  0.5   0:35.89 slapd
 2897 root      15   0  6344 3512 1920 S  0.0  0.1   0:01.40 snmpd
 2771 haldaemo  18   0  5176 3308 2108 S  0.0  0.1   0:00.11 hald
31370 myuser    15   0  3576 2004 1224 S  0.0  0.1   0:00.01 bash
31367 root      16   0  6404 1932 1572 S  0.0  0.0   0:00.02 sshd
 2940 root      15   0  3176 1904 1272 S  0.0  0.0   0:00.15 bash
 2735 root      19   0  5800 1576  852 S  0.0  0.0   0:00.00 mount.smbfs
 2727 root      17   0  5796 1568  852 S  0.0  0.0   0:00.00 mount.smbfs
 2738 root      20   0  5796 1568  852 S  0.0  0.0   0:00.00 mount.smbfs
31369 myuser    15   0  6404 1212  852 R  0.0  0.0   0:00.00 sshd
31380 myuser    15   0  2308 1120  876 R  0.0  0.0   0:00.01 top
 2750 root      18   0  3824 1116  820 S  0.0  0.0   0:00.06 sshd
 2883 root      15   0  2488 1008  820 S  0.0  0.0   0:13.61 vmware-guestd
 2772 root      25   0  2868  992  860 S  0.0  0.0   0:00.00 hald-runner
 2783 root      15   0  2920  968  852 S  0.0  0.0   0:00.12 hald-addon-stor
 2781 myuser    25   0  2112  900  784 S  0.0  0.0   0:00.00 hald-addon-acpi

In theory, which are the numbers in the table which should add up to the figure in the summary?

score 2 · Accepted Answer · answered Dec 09 '09 at 09:20

2

It'll be used by the system cache. If you run the free command, you'll see what's been used by buffers/cache. This isn't something to worry about (it's normal). It's just the kernel attempting to efficiently use your available memory.

answered Dec 09 '09 at 09:20

rodjek

3,327
17
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You've missed the `top` output, where `java` process takes 60% memory. – kolypto Dec 09 '09 at 10:24
1

Presumably, the OP is capable of reading that and is asking where the rest of his memory went (assumption). May be wrong. – rodjek Dec 09 '09 at 11:34

score -1 · Answer 2 · answered Dec 09 '09 at 10:23

-1

java: 59.6 %MEM, RES: 2.2g

This means java takes ~60% of your memory (2.2g actually): you have a memory leak in some java application.

Buffers take only about 25MiB:

answered Dec 09 '09 at 10:23

kolypto

11,058
12
54
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And you missed the 1.2GB of cache. – rodjek Dec 09 '09 at 11:36

How should I read these figures from top? Where's the memory gone?

2 Answers2