Size limit of table field ?

[Martin Baxter]

>Mark Brownell wrote:
>On Wednesday, October 6, 2004, at 10:26 AM, Martin Baxter wrote:
>
>> I can confirm that it's true even for a 68k standalone running on
>> system 7.6
>>
>> If you increase the application memory, you can actually make the
>> situation
>> worse, because it leaves less for the system heap, which is where the
>> application is actually getting memory from (as I understand it).
>> I was quite vexed by this when I first saw it (but I changed my
>> medication
>> and have calmed down now;-)
>>
>> Martin Baxter
>
>So if I understand this if I allocate more memory for my standalone
>apps created for classic Mac OS in order to make room for media running
>in my standalone I would actually be making less room for my standalone
>application and media? Of course I will need to test this. Does the
>standalone builder in Mac OS classic running on classic set a proper
>memory size for each standalone that it builds?
>
>This is interesting because some users only have 32 meg systems.
>
>Mark
>

You're correct. The application memory you allocate is not used for
data/stacks/media. I think only the engine etc is loaded into there, and if
you allocate extra application memory it won't be used for anything, it
will just reduce the total amount of memory available to the rest of the
system (which includes your app's components).

I'm still using RR2.1.2 so can only go by that but the default app memory
allocation for MacOS in the SB is 8000K and that seems about right. You can
enter a figure for it yourself in the SB if you think it's insufficient,
but I've found 8000K is OK for my needs.

A largeish Rev app I have running on the machine I'm typing this on (which
is a Quadra with 36mb ram) uses about 75% of that allocation, and that
figure stays more or less constant no matter how you use the app. However,
my app also grabs about 10MB of system heap during startup, presumably as a
result of my initialisation handlers loading stacks and data. So if it were
running in its own exclusive memory partition it would need about 17MB just
to start up.

Running under actual MacOS 7.6 is enlightening because "about this
computer" shows the system memory fluctuating as applications grab system
heapspace during operation, which I haven't seen displayed in later OS
versions.

I've never tried the TMEM resource hack that Richard Gaskin described
elsewhere but I have no reason to doubt it works if you really need to make
an application stay religiously in its own ram playpen.

Martin Baxter