From some MS optimization tips in VFP a while back, you should set it to about 1/3 of total memory like:
SYS(3050, 1, VAL(SYS (3050, 1, 0)) / 3)
If your web service is an mtdll, you might want to take a look at the generic project hook in downloads that transparently Unloads the mtdll when you re-compile. Also for interactive debugging of mtdlls, check out the following (although I haven't tried in a VFP web service):
http://www.theproblemsolver.nl/aspdevelopmentanddebugging/index.htm

>I couldn't figure out whether a WS would be considered FG or BG, so I tried this as the WS method:
>
>FUNCTION test(cfile) as String
> IF TYPE("cfile") = "C" and FILE(cfile)
> SYS(3050,1,15000)
> SYS(3050,2,15000)
> cxml = FILETOSTR(cfile)
> RETURN STRCONV(cxml,13)
> ELSE
> RETURN " "
> ENDIF
>ENDFUNC
>
>Still no luck. A 173k file fails, but a 75k file works fine.
>
>The error message I get is:
>OLE IDispatch exception code 0 from mpgorderproc.SMOrder
>mpgorderproc.SMOrder: .test
>d:\comobj\orderproc\mpgorderproc.prg Error in line 787
>-1073741571
>
>
>MPGOrderproc is the project name. SMOrder is the class.
>d:\comobj\orderproc\ is the location of the WS DLL. 787 is the line of code that runs STRCONV.
>
>Any other ideas? Web Service troubleshooting is tough! There aren't a lot of resources available yet.
>
>Thanks!
>Brian
>
>
>
>
>
>>Actually, it may be running out of memory - you may need to use SYS(3050...) to limit the amount of memory used. This usually happens with batch type jobs in VFP on Win2k,nt, xp ...
>>>We're using a web service to process some data, build a PDF, then change the PDF into a base64 encoded string using STRCONV(cfile,13). The first 2 parts work great, but the STRCONV fails on files about 50k+.
>>>
>>>Has anyone experienced similar troubles?
>>>
>>>Is there a registry setting (SOAP or IIS) that limits the amount of RAM that can be used by a web service?
>>>
>>>Or perhaps there is another way (fast) to base64 encode a file?
>>>
>>>Thanks!
>>>Brian