Highlighted
Anonymous_User Absent Member.
Absent Member.
1010 views

More Memcalc questions

Before running Memcalc on my NW 6.5 SP4 server, I checked the size of
DS by looking in Segstats.txt. It was in the Top 5 Memory Consuming
NLM's at 29 MB of memory. (This is a small business server.) After
running Memcalc, I checked the _NDSDB.INI and found the following
lines:

cache=33554432
preallocatecache=true

I didn't see the other parameters that are listed in Hamish's document
such as 'cacheadjustinterval, cachecleanupinterval or
blockcachepercent. Should this be a concern?

Now when I look at the DS.NLM memory in segstats, it is shown as 40 MB.
I thought that by using the _NDSDB.INI file, I was 'locking' the amount
of memory available to NDS to the 33.5 MB number shown above but that
doesn't seem to be the case here. What am I missing?

What happens now if eDir grows and bumps into the size we have
pre-allocated for the eDir cache? Do I get a warning or anything?

One other question (I posted accidentally as a reply to another message
in a completely unrelated topic-duh) are the calculations in Hamish's
article. Looking at Hamish's Document on Memcalc, I can't get the
same numbers he gets for his example for the FCMS value. Since the
server has more than 3.2 GB, the formula according to the doc should
be: (P - (P / 10) - NC - U) = 3757543552 - (3757543552/10) - 565481472
- 559448064 = 2,256,859,661 but the doc says it should be
2,256,535,552. What am I missing?

Thanks,

Dan

Labels (2)
0 Likes
9 Replies
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Daniel,

> Before running Memcalc on my NW 6.5 SP4 server, I checked the size of
> DS by looking in Segstats.txt. It was in the Top 5 Memory Consuming
> NLM's at 29 MB of memory. (This is a small business server.) After
> running Memcalc, I checked the _NDSDB.INI and found the following
> lines:
>
> cache=33554432
> preallocatecache=true
>
> I didn't see the other parameters that are listed in Hamish's document
> such as 'cacheadjustinterval, cachecleanupinterval or
> blockcachepercent. Should this be a concern?


The other values are basically defaults - I just set them in the same
way that iMonitor would if you fixed the cache size using it instead of
memcalc.

> Now when I look at the DS.NLM memory in segstats, it is shown as 40 MB.
> I thought that by using the _NDSDB.INI file, I was 'locking' the amount
> of memory available to NDS to the 33.5 MB number shown above but that
> doesn't seem to be the case here. What am I missing?


The cache = 33554432 sets the size od the eDir cache to 32MB (memcalc
takes the current DS.NLM footprint and sets the cache size to that
rounded up to the next multiple of 16MB) so at 29MB footprint, the cache
size is rounded up and fixed at 32MB. The other 8MB is the actual DS
executable code and other data- its the cche size thats fixed, not the
total footprint of the DS nlm.

> What happens now if eDir grows and bumps into the size we have
> pre-allocated for the eDir cache? Do I get a warning or anything?


No - it'll just continue to operate at the fixed size cache. If you make
any significant changes to any server where the cache size has been
fixed - adding many new objects or additional replicas,it would be worth
while to remove the fixed cache size, and let DS readjust to use the
unlimited cache, then reset to fixed based on what it grows to.


> One other question (I posted accidentally as a reply to another message
> in a completely unrelated topic-duh) are the calculations in Hamish's
> article. Looking at Hamish's Document on Memcalc, I can't get the
> same numbers he gets for his example for the FCMS value. Since the
> server has more than 3.2 GB, the formula according to the doc should
> be: (P - (P / 10) - NC - U) = 3757543552 - (3757543552/10) - 565481472
> - 559448064 = 2,256,859,661 but the doc says it should be
> 2,256,535,552. What am I missing?


I suspect the difference is in directly subtracting the U value, where
as I actually round the U value to a MB boundary value first - but I'll
need to sit down and go over the numbers again to be sure.


--
Hamish Speirs
Novell Support Forums Volunteer Sysop.

http://haitch.net

(Please, no email unless requested. Unsolicited support emails will
probably be ignored)
0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Thanks, Hamish, for the quick response.

On the DS Cache issue, what should I do to remove the fixed cache size?
Just remove the _NDSDB.INI file? Then reboot the server and watch to
see what the DS Cache settles down to?

As for the calculations, what you say makes sense. I was just trying
to check my understanding against the example numbers that you provided
and when I didn't get the same answers as you I thought I must be doing
something wrong.

BTW, running your Memcalc fixed a NW 6.5 SP5 server for me today. This
server even had the post SP5 server.exe on it and it still was running
out of cache buffers! It seems to me that Novell has really screwed up
NetWare memory tuning. We never had these problems before.

Thanks,

Dan

0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Dan,

> Thanks, Hamish, for the quick response.


Was good timing - just happened to be passing through 😉

> On the DS Cache issue, what should I do to remove the fixed cache size?
> Just remove the _NDSDB.INI file? Then reboot the server and watch to
> see what the DS Cache settles down to?


You can either edit the _ndsdb.ini file and remove the line, or use
iMonitor to set it back to a dynamic cache.

> As for the calculations, what you say makes sense. I was just trying
> to check my understanding against the example numbers that you provided
> and when I didn't get the same answers as you I thought I must be doing
> something wrong.


The doc and the app went through a number of iterations while I tweaked
it - guess the doc got out of sync with the program and exact algorithm.
Will tidy up the doc and more fully explain the calcs.

>> BTW, running your Memcalc fixed a NW 6.5 SP5 server for me today. This

> server even had the post SP5 server.exe on it and it still was running
> out of cache buffers!


It will happen, but the new server.exe is the best Novell has put out. I
still think its a bit trigger happy on its "tuning" and simplistic in
its approach, but its definitely better.

>It seems to me that Novell has really screwed up
> NetWare memory tuning. We never had these problems before.


The memory tuning algorithms were introduced to adapt to the changing
role of NetWare. As it changed from pure F&P, to directory server,
database server, java app server, the demands on memory changed. The
memory tuning is an attempt to meet the many different and contradictory
demands - its a compromise, and like many compromises, not good news for
specific situations. If your environment is sufficiently stable, then I
recommend manual tuning to your environment.

--
Hamish Speirs
Novell Support Forums Volunteer Sysop.

http://haitch.net

(Please, no email unless requested. Unsolicited support emails will
probably be ignored)
0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Hamish, I have been watching this new NW 6.5 SP5 with post SP5
server.exe and NSS patches for the last couple weeks or so. I ran your
memcalc utility on it right after we brought it up and that has helped
but I notice a slow but inexorable decrease in cache buffers over the
last 2 weeks.

The Server is an HP Proliant ML350 with 4 GB of RAM. Other than
NetWare we are running Backup Exec 9.2 (latest build) as well as
ZENworks 6.5.

This is the trend I am seeing for Current cache buffers. (Original
Cache buffers were 916,371):

Immediately after running Memcalc on 6/14 - 483,815
6/15 - 375,526
6/16 - 375,272
6/19 - 375,280
6/20 - 374,952
6/21 - 374,931
6/22 - 374,890

Also Available Logical Space has decreased somewhat but is still just
above 800 MB.

Is this what you would normally expect to see on a NW 6.5 SP5 server
even after manually tuning the memory?

Dan

0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Daniel C. Hunt wrote:

>I ran your
>memcalc utility on it right after we brought it up


Hamish is gonna tell you that you need to let the server run for a day or
two before you run memcalc or it won't be accurate

--
Joe Moore
Novell Support Forums SysOp
http://just.fdisk-it.com
http://www.caledonia.net/jmdns.html
http://www.caledonia.net/nesadmin.html
http://www.caledonia.net/jmttb.html
0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Joe,

> Hamish is gonna tell you that you need to let the server run for a day
> or two before you run memcalc or it won't be accurate


Yep.


--
Hamish Speirs
Novell Support Forums Volunteer Sysop.

http://haitch.net

(Please, no email unless requested. Unsolicited support emails will
probably be ignored)
0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Daniel,

> Hamish, I have been watching this new NW 6.5 SP5 with post SP5
> server.exe and NSS patches for the last couple weeks or so. I ran your
> memcalc utility on it right after we brought it up


As Joe said, you need to let the server run for a while, at least a day
preferably, before running memcalc, otherwise the values its using for
the calculaions will generally be too low.

> Also Available Logical Space has decreased somewhat but is still just
> above 800 MB.


I'd actually expect logical memory to be lower than that.


--
Hamish Speirs
Novell Support Forums Volunteer Sysop.

http://haitch.net

(Please, no email unless requested. Unsolicited support emails will
probably be ignored)
0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Hamish, so after letting the server run for a while, with the settings
that Memcalc.nlm has put in, can I run it again and get 'better' values
that it will write to the server Set parameters?

Or do I have to somehow undo the set parameters that Memcalc had set
and then let the server run for a couple days and then re-run Memcalc?
This would be difficult because without the Memcalc values that are
currently there, the server seems to have very low cache buffers.

Thanks,

Dan

0 Likes
Anonymous_User Absent Member.
Absent Member.

Re: More Memcalc questions

Dan,

> Hamish, so after letting the server run for a while, with the settings
> that Memcalc.nlm has put in, can I run it again and get 'better' values
> that it will write to the server Set parameters?


Not really, with the the existing memcalc settings the server won't use
memory properly.

> Or do I have to somehow undo the set parameters that Memcalc had set
> and then let the server run for a couple days and then re-run Memcalc?
> This would be difficult because without the Memcalc values that are
> currently there, the server seems to have very low cache buffers.


If you can run the server with the default settings, that would be
preferable - the following ncf will reset the settings:

set Auto Tune Server Memory=on
set File Cache Maximum Size=2147483648
set VM Cache Pool Percentage=80
set VM Cache Pool Maximum Pages Percentage=0
set FS Cache Pool Minimum Pages=1000
set FS Cache Pool Desired Pages=1250
set FS Cache Pool Lots of Pages=1500

Reset these values, then run the server for a reasonable amount of time,
then use Memcacl.

--
Hamish Speirs
Novell Support Forums Volunteer Sysop.

http://haitch.net

(Please, no email unless requested. Unsolicited support emails will
probably be ignored)
0 Likes
The opinions expressed above are the personal opinions of the authors, not of Micro Focus. By using this site, you accept the Terms of Use and Rules of Participation. Certain versions of content ("Material") accessible here may contain branding from Hewlett-Packard Company (now HP Inc.) and Hewlett Packard Enterprise Company. As of September 1, 2017, the Material is now offered by Micro Focus, a separately owned and operated company. Any reference to the HP and Hewlett Packard Enterprise/HPE marks is historical in nature, and the HP and Hewlett Packard Enterprise/HPE marks are the property of their respective owners.