topic Re: Memory Limit in SAS Programming

Memory Limit

Marmar — Thu, 26 Jul 2018 19:41:45 GMT

Hi all,

I've got problem with SAS performance on my PC. When processing big data, it works very slow. At first, it shows the message of SAS not responding then after minute, the results are displayed! I've tried to increase the limit of memory by the syntax of : -Memsize=n but got error!

Any comment on this problem would be appreciated greatly.

Thank you

Re: Memory Limit

ChrisBrooks — Thu, 26 Jul 2018 21:05:58 GMT

Try -memsize=max in the SAS invocation from the command line (this gives SAS as much memory as it needs subject to what is available on your machine).

Re: Memory Limit

Astounding — Thu, 26 Jul 2018 21:57:12 GMT

Speed can depend on many factors, and memory is only one of those. (Unfortunately, poor programming technique ranks high on the list.) If you want more specific advice, post the log of a slow-running program.

Re: Memory Limit

ballardw — Thu, 26 Jul 2018 22:10:58 GMT

Is your data on your machine or a remote location and accessed over a network? Network traffic can have an impact.

How "big" is big? Number of records and variables.

Also, are using a stand alone version of SAS or connecting to a SAS server?

How did you attempt to use -Memsize=n? It would have to be either in the SAS configuration file or on a command line/ program object as the option must be set at start up and cannot be changed while running. In a server environment the Admin of the server would control users memsize.

Re: Memory Limit

ChrisNZ — Thu, 26 Jul 2018 23:13:41 GMT

@ChrisBrooks this gives SAS as much memory as it needs subject to what is available on your machine

MEMSIZE includes paging space, so is pretty much illimited.

REALMEMSIZE is the setting used to control RAM usage.

The documentation is confusing.

Re: Memory Limit

Marmar — Thu, 02 Aug 2018 19:24:02 GMT

Hi,

Thank you for your reply and sorry for delay in replying your message!.

I've tried -memsize=max on the command line but got this error message:

3 -MEMSIZE=max;
-
180

ERROR 180-322: Statement is not valid or it is used out of proper order.

I'm just wondering if I've written the syntax properly or there is another
solution?

Thank you,
Marmar

Re: Memory Limit

Marmar — Thu, 02 Aug 2018 19:33:02 GMT

Hi,

Thank you for your comment and sorry for delay in replying!.

Actually, I don't get any message error on the log, just the software works
slowly when running a command of Proc Print a data file of about 64,000 and
I see the message on top of page indicating SAS not responding. Then after
a while it process the command and get the results!

Thanks,
Marmar

Re: Memory Limit

Marmar — Thu, 02 Aug 2018 19:40:02 GMT

Hi,

Thank you for your comment and sorry for delay in replying!.

I'm using SAS on the PC and data file is stored on my machine which
containing about 64,000 with 20 variables. Actually, I just get error with
the command of Proc Print and the number of variable about 6. I see no
error message on the Log, just see the message on top indicating SAS not
responding. After few minutes the command is running and get the results.

I used -Memsize=max before programming!

Marmar

Re: Memory Limit

Marmar — Thu, 02 Aug 2018 19:41:02 GMT

Hi,

Thank you for your comment and sorry for delay in replying!.

I've tried REALMEMSIZE as well but got no improvement.

Thanks,
Maryam

Re: Memory Limit

Astounding — Thu, 02 Aug 2018 20:08:30 GMT

This may not solve the entire problem, but there are options on PROC PRINT that force SAS to look through the entire data set twice. You didn't post the log, so I can't see what options you used. Try adding a FORMAT statement that applies a format to all 6 variables, and see how much impact that has.

Re: Memory Limit

hashman — Thu, 02 Aug 2018 20:16:27 GMT

Proc PRINT against a data set like what you described takes no more than 500 kilobytes of memory. Since I can't imagine your computer having less than 1 gigabyte of memory, i.e. at least 2000 times more than you need, poor performance you're observing has nothing to do with insufficient memory and lies elsewhere. For example, If you're printing all 64,000 observations (can't imagine whey that would be necessary), you may want to check if the destination to which you're sending the output isn't somehow constrained.

Paul D.