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Ninode parameter in HP-UX 11.00

 
MR Dorobantu Dragos
Frequent Advisor

Ninode parameter in HP-UX 11.00

Hello,

I have problems with my system regarding performances. My system have 4GB RAM and 4GB swap
My system has some difficulties when ninode is at the maximum value. Strange is that this value was increased from 1916 to 9580 and the problem was not solved because the maximum value is reached from time to time.
Also the with sar –d 5 5 when the max value for ninode is reached the disk busy value is 99% or 100%.
What can I do to detect what is the problem and what are the solutions?


[btsrv-n1]:/var/adm # sar -d 5 5

HP-UX btsrv-n1 B.11.00 U 9000/800 10/08/04

15:56:50 device %busy avque r+w/s blks/s avwait avserv
15:56:55 c1t2d0 8.60 0.50 23 576 4.33 9.00
c2t2d0 4.20 0.50 22 572 4.36 5.32
c16t0d4 98.00 1.03 835 19021 5.41 4.20
c16t0d7 89.20 0.96 848 25718 5.64 3.72
15:57:00 c1t2d0 10.60 0.50 26 596 4.69 9.01
c2t2d0 5.80 0.50 23 571 4.83 5.73
c16t0d4 98.20 1.68 947 23102 5.78 4.52
c16t0d7 94.60 0.98 1004 30230 5.44 3.39
15:57:05 c1t2d0 9.58 0.50 22 521 5.27 8.85
c2t2d0 4.99 0.50 19 489 5.32 5.45
c16t0d4 98.80 1.98 1079 26482 6.07 4.14
c16t0d7 93.01 0.86 884 28302 5.33 3.91
10 REPLIES 10
RAC_1
Honored Contributor

Re: Ninode parameter in HP-UX 11.00

The kernel parameter ninode applies only to HFS file systems. How many HFS file systems do you have??

Also what applications/programs you run on these file systems?? Do they do a lot of reads/writes to these disks??

Anil
There is no substitute to HARDWORK
MR Dorobantu Dragos
Frequent Advisor

Re: Ninode parameter in HP-UX 11.00

I think my fyle systems are Vxfs not HFS.
How can I monitorize that?
RAC_1
Honored Contributor

Re: Ninode parameter in HP-UX 11.00

Most of the systems will have /stand as only HFS file system. For vxfs, the inodes are created dynamically. What is the exact error message that you get??

The vx_ninode is the kernel parameter that controlls the inode creation for vxfs file systems. If set to 0, the inodes are created
dynamically.

Which OS version do you have?? On vxfs version 3.3, in order to check the current usage of vxfs inodes, you can do as follows.

echo "vx_cur_ninode/D" | adb

Anil
There is no substitute to HARDWORK
MR Dorobantu Dragos
Frequent Advisor

Re: Ninode parameter in HP-UX 11.00

The requests from the clients are not served and the client application goes offline. The application is some Informix database.
I observed this error when sar â v shows ninode reach the max value and when the disk are busy to 99%(sar â d ).
Also the kernel parameter nfile was incresed till 4224 and is not reached.

OS version is 1
RAC_1
Honored Contributor

Re: Ninode parameter in HP-UX 11.00

What is the exact error message??
Check /var/adm/syslog/syslog.log
check dmesg.

Also the disks that are quite bust, which lvol they belong to?? And what is the fs created on these lvols-hfs/vxfs??

Anil
There is no substitute to HARDWORK
MR Dorobantu Dragos
Frequent Advisor

Re: Ninode parameter in HP-UX 11.00

In syslog I found one error:
vmunix: file: table is full
but when the client application start to goes offline I do not see anything in syslog.log. That error appear when nfile reach the max value.

The fs is vxfs and SO is 11.00

Prashant Zanwar_4
Respected Contributor

Re: Ninode parameter in HP-UX 11.00

So your bet is now to look at nfile parameter along with maxfiles & maxfiles_lim.

maxfiles and maxfiles_lim :
Soft and hard limits on per-process file opens â quite often set too low. Bump
maxfiles and maxfiles_lim to 200 if they're not already 200, and higher on Web and
file servers (2000). Bump them up if you encounter "Too many open files" program
failures. For 11.11, maxfiles_lim was one of the new â dynamic tunables,â which means
you can bump it with the kmtune(1M) command... see our discussion of dynamic kernel parameters at the end of this section.

maxuprc:
Limit on processes for non-root users. Set this to 200 if its not already more than that.Fifty processes per user default limit is often not enough. This is another dynamic
tunable in 11.11.

maxusers:
This parameter has nothing to do with the maximum number of users. Don't try to figure
it out. A good value for most systems to start with is 128. This is used to size many
other tunables, by default, so don't go overboard. Normally 512 would be the max
maxusers we'd recommend. By default, this is used in a bunch of those sam configuration parameter formula thingys to size different other tunables: so watch it.

nfile:
The maximum number of concurrent file opens (that is, not the number of open files but
the number of concurrent open()s) on the system. The default formula usually works
this out to around this value, but 3000 is a pretty good starting point. If you have a lot of filesystem activity, you can bump this up higher without issues (a large Informix shop had this set to 80000!). Bump nfile up if you see high File Table utilization (>80 percent) in Glance (System Tables Report) or get "File table overflow" program errors. Use a similar approach for nflocks (max file locks). If you are configuring a big filesystem server
then you're more likely to want to bump up these limits.

Thanks
"Intellect distinguishes between the possible and the impossible; reason distinguishes between the sensible and the senseless. Even the possible can be senseless."
RAC_1
Honored Contributor

Re: Ninode parameter in HP-UX 11.00

The error message is about nfile kernel parameter is hitting the limit.

The real time usage of it can be seen with following commands.

sar -v 5 5
glance -t

Now your setting for nfile as you siad is 4224. Which a very low value for a system running a database. What else you run on this system??? Set it to a high value. Say 20000. Else, use a formulae to set the value. Goto SAM, kernel config and configurable kernel parameters and chose "use formulae" for this parameter.
(16*(NPROC+16+MAXUSERS)/10+32+2*(NPTY+NSTRPTY+NSTRTEL))

After modifying it, observe the usage as infomred about. (sar -v and glance -t)

Also what is your buffer cache setting??? Do you use dynamic buffer cache??(use of dbc_max_pct and dbc_min_pct) or do you use static buffer cache?? (use of nbuf and/or bufpages)

Anil
There is no substitute to HARDWORK
MR Dorobantu Dragos
Frequent Advisor

Re: Ninode parameter in HP-UX 11.00

So,

maxfiles = 120 (I will increase to 200 )
maxfiles_lim = 1024
maxuprc = 800
maxusers = 192
dbc_max_pct = 50
dbc_min_pct = 0

Should I modify dbc_max_pct to 0?


RAC_1
Honored Contributor

Re: Ninode parameter in HP-UX 11.00

maxfiles = 120 (Set it to 1024)
maxfiles_lim = 2048
maxuprc = 2000
maxusers = 192
dbc_max_pct = 15
dbc_min_pct = 5

Set as above and post.

Anil
There is no substitute to HARDWORK