Hello,
The original question was :
>
> I'm running DU 4.0 on an alphastation 250 4/266 with 192 Mb of memory.
>
> There is only one user but many processes are running in background. With
> dxsysinfo, I've got only 8% of free memory . With syd, I've got 38.5 Mb which
> seems to me more reasonnable.
>
> How is dxsysinfo working ? Could I have an exact result on memory usage ?
>
> Thanks
>
I've got two answers from Digital people, thank you :
----------------------------
alan_at_nabeth.cxo.dec.com
I think vmstat will print a better overview of memory
usage:
memory
act free wire
3002 3082 1169
This shows the active memory, free memory and wired
memory (used by the kernel, can't be paged). There
is a graphic program called vmubc that should be
available on our FTP server, which will give a more
detailed breakdown.
The memory could be just be tied up in the buffer
cache since it will use all of free memory given
the chance. As long as the system isn't paging,
the low amount of free memory isn't really a problem.
As memory is needed for process data, it will taken
the chance. As long as the system isn't paging,
the low amount of free memory isn't really a problem.
As memory is needed for process data, it will taken
away from the buffer cache.
------------------------------------
Hi,
The Free memory dial on dxsysinfo although technically correct, is not very useful
and is misleading.
The value of this dial almost always stays at 1-2% on a lightly used system because
the goal of the operating system is to use all the memory by keeping the Unified
Buffer Cache as big as possible. The dial gets its %free value by dividing the
vmstat free memory field into the total memory field.
I plan on changing what the memory dial reports in
an upcoming release of Steel. What I think should be shown is
the percentage of memory not reserved (ie, not referenced by a
process).
--
Phil Stallone
Digital Equipment Corp.
pjs_at_unx.dec.com
Received on Tue Sep 03 1996 - 17:50:23 NZST