Bind Memory Usage

glober

Hi,

I'm having some issues with bind memory usage.

This is memory stats before starting bind:

[root@us ~]# free -m
             total       used       free     shared    buffers     cached
Mem:           256         25        230          0          0          0
-/+ buffers/cache:         25        230
Swap:            0          0          0

This is after starting the bind:

[root@us ~]# free -m
             total       used       free     shared    buffers     cached
Mem:           256         58        197          0          0          0
-/+ buffers/cache:         58        197
Swap:            0          0          0
[root@us ~]#

33 MB difference in memory. The top command shows bind is using 3716 = 3.63 MB only. My question is where other 30 MB memory gone.

[root@us ~]# top -b -n1
top - 15:53:33 up 10:59,  1 user,  load average: 0.00, 0.00, 0.00
Tasks:  15 total,   1 running,  14 sleeping,   0 stopped,   0 zombie
Cpu(s):  0.2%us,  0.1%sy,  0.0%ni, 99.6%id,  0.2%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:    262144k total,    60412k used,   201732k free,        0k buffers
Swap:        0k total,        0k used,        0k free,        0k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
    1 root      15   0 10364  732  620 S  0.0  0.3   0:00.46 init
 1983 root      18   0 20892 1188  596 S  0.0  0.5   0:00.00 crond
 2024 root      18   0 46756  816  428 S  0.0  0.3   0:00.00 saslauthd
 2025 root      18   0 46756  548  160 S  0.0  0.2   0:00.00 saslauthd
 4019 root      18   0 86080 3356 2608 S  0.0  1.3   0:00.58 sshd
 4021 root      15   0 12076 1680 1316 S  0.0  0.6   0:00.11 bash
 5267 root      15  -4 12792  760  440 S  0.0  0.3   0:00.00 udevd
 5376 root      15   0  6816  612  496 S  0.0  0.2   0:00.00 syslogd
 5535 root      18   0 63544 1168  608 S  0.0  0.4   0:00.00 sshd
 5571 root      17   0 21660  924  712 S  0.0  0.4   0:00.00 xinetd
23621 root      18   0 14964  856  512 S  0.0  0.3   0:00.00 proftpd
23825 root      18   0  202m 6564 3264 S  0.0  2.5   0:00.00 httpd
23826 apache    23   0  202m 3952  628 S  0.0  1.5   0:00.00 httpd
24241 named     25   0 88456 3716 1816 S  0.0  1.4   0:00.00 named
24250 root      15   0 12620 1072  840 R  0.0  0.4   0:00.00 top

after stopping the bind memory returns to 25 MB.

any help would be highly appreciated.

glober

I have just checked this on another vps and its the same... 35 MB memory used before and 75 MB memory used after starting Bind. Top command is showing 3.38MB used by bind. Above VPS does not have any zones loaded however this one has 5 zones.

I wonder if someone can explain this?

drmike

I wonder if it's loading a huge zone file for some reason. How many zones are we looking at?

edit: Some discussion here: http://serverfault.com/questions/113166/any-way-to-reduce-bind9-memory-footprint

Nothing much really but just a confirmation that the chunk of memory used is normal it appears.

glober

No zones for first VPS I was just setting it up and only 5 zones for 2nd VPS.... even if its loading huge zone file the memory should be reflected in Top command is not it?

I'm worried why the memory is not justified.

glober

This is rndc status for first vps:

[root@us ~]# rndc status
number of zones: 0
debug level: 0
xfers running: 0
xfers deferred: 0
soa queries in progress: 0
query logging is OFF
recursive clients: 0/1000
tcp clients: 0/100
server is up and running

Go59954

It takes that much and more, and that increases if you load more zones. But there are alternatives to BIND that take much less memory.

kylix

MaraDNS for example.

dmmcintyre3

BIND allocates much more memory than it really needs. Older OpenVZ memory limits are based on allocation, not the real usage.

yomero

OpenVZ.. yeah ¬¬ You must be grateful, because in some processes, the memory used is almost the VIRT column in your top (88 mb in your case)

glober

I've installed NSD took only 10MB memory.

Infinity

NSD is neat