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Re-purposing vm parameter 23 in Spur?

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Eliot Miranda-2

Re-purposing vm parameter 23 in Spur?

Hi All,

right now vm parameter 23 is defined to be:

23 bytes of extra memory to reserve for VM buffers, plugins, etc.

but is ignored by all the VMs (AFAIA). I would like to reinterpret this in Spur to be the minimum amount of headroom to make available on startup. I expect this is useful for really small platforms where one wants to control the ammount of free space on startup to be quite small. Given that the field is ignored I like putting it to a more useful purpose. Objections?
--

best,

Eliot

johnmci

Re: Re-purposing vm parameter 23 in Spur?

23 was used in os 7/8/9? back in the last millennium to ensure the allocation of memory for the image wouldn't consume all the memory in the application space, thus leaving no memory for third party plugs which could required non-trival free memory for malloc. So yes a good reuse..

Also see http://en.wikipedia.org/wiki/Mac_OS_memory_management

On Mon, Mar 23, 2015 at 12:45 PM, Eliot Miranda <[hidden email]> wrote:

Hi All,

right now vm parameter 23 is defined to be:

23 bytes of extra memory to reserve for VM buffers, plugins, etc.

but is ignored by all the VMs (AFAIA). I would like to reinterpret this in Spur to be the minimum amount of headroom to make available on startup. I expect this is useful for really small platforms where one wants to control the ammount of free space on startup to be quite small. Given that the field is ignored I like putting it to a more useful purpose. Objections?
--
best,
Eliot

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John M. McIntosh <[hidden email]> https://www.linkedin.com/in/smalltalk
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