Re: patch: tsearch - some memory diet

2010/9/7 Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>:
> On 07/09/10 19:27, Teodor Sigaev wrote:
>>>
>>> on 32bit from 27MB (3399 blocks) to 13MB (1564 blocks)
>>> on 64bit from 55MB to cca 27MB.
>>
>> Good results. But, I think, there are more places in ispell to use
>> hold_memory():
>> - affixes and affix tree
>> - regis (REGex for ISpell, regis.c)
>
> A more general solution would be to have a new MemoryContext implementation
> that does the same your patch does. Ie. instead of tracking each allocation,
> just allocate a big chunk, and have palloc() return the next n free bytes
> from it, like a stack. pfree() would obviously not work, but wholesale
> MemoryContextDelete of the whole memory context would.
>
> I remember I actually tried this years ago, trying to reduce the overhead of
> parsing IIRC. The parser also does a lot of small allocations that are not
> individually pfree'd. And I think it helped a tiny bit, but I didn't pursue
> it further. But if there's many places where it would help, then it might
> well be worth it.

I sent patch last year - simpleAllocator, and this idea was rejected.
But now I dislike this idea too. This is unclear, and some forgotten
"free" calling can do problems. This is more simple, more readable and
secure.

Regards

Pavel Stehule

>
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>  Heikki Linnakangas
>  EnterpriseDB   http://www.enterprisedb.com
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