| Lists: | pgsql-hackers |
|---|
| From: | Gavin Sherry <swm(at)linuxworld(dot)com(dot)au> |
|---|---|
| To: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | Memory management, palloc |
| Date: | 2001-03-08 11:28:50 |
| Message-ID: | Pine.LNX.4.21.0103082204580.9685-100000@linuxworld.com.au |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Lists: | pgsql-hackers |
Hi guys,
I've been looking through the memory management system today.
When a request is made for a memory memory chunk larger than
ALLOC_CHUNK_LIMIT, AllocSetAlloc() uses malloc() to give the request its
own block. The result is tested by AllocSetAlloc() to see if the memory
was allocated.
Irrespective of this, a chunk can be returned which has not had memory
allocated to it. There is no testing of the return status of
palloc() through out the code.
Was/has this been addressed?
Thanks
Gavin
| From: | Karel Zak <zakkr(at)zf(dot)jcu(dot)cz> |
|---|---|
| To: | Gavin Sherry <swm(at)linuxworld(dot)com(dot)au> |
| Cc: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Memory management, palloc |
| Date: | 2001-03-08 14:54:29 |
| Message-ID: | 20010308155429.A11790@ara.zf.jcu.cz |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Lists: | pgsql-hackers |
On Thu, Mar 08, 2001 at 10:28:50PM +1100, Gavin Sherry wrote:
> Hi guys,
>
> I've been looking through the memory management system today.
>
> When a request is made for a memory memory chunk larger than
> ALLOC_CHUNK_LIMIT, AllocSetAlloc() uses malloc() to give the request its
> own block. The result is tested by AllocSetAlloc() to see if the memory
> was allocated.
>
> Irrespective of this, a chunk can be returned which has not had memory
> allocated to it. There is no testing of the return status of
> palloc() through out the code.
I don't understand. If some memory is not obtain in AllocSetAlloc()
all finish with elog(ERROR). Not exists way how return insufficient
space. Or not?
Karel
--
Karel Zak <zakkr(at)zf(dot)jcu(dot)cz>
http://home.zf.jcu.cz/~zakkr/
C, PostgreSQL, PHP, WWW, http://docs.linux.cz, http://mape.jcu.cz
| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Gavin Sherry <swm(at)linuxworld(dot)com(dot)au> |
| Cc: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Memory management, palloc |
| Date: | 2001-03-08 15:14:12 |
| Message-ID: | 25596.984064452@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Lists: | pgsql-hackers |
Gavin Sherry <swm(at)linuxworld(dot)com(dot)au> writes:
> I've been looking through the memory management system today.
> When a request is made for a memory memory chunk larger than
> ALLOC_CHUNK_LIMIT, AllocSetAlloc() uses malloc() to give the request its
> own block. The result is tested by AllocSetAlloc() to see if the memory
> was allocated.
> Irrespective of this, a chunk can be returned which has not had memory
> allocated to it. There is no testing of the return status of
> palloc() through out the code.
What's your point?
palloc() does not have the same specification as malloc. It guarantees
to return allocated memory, or elog trying.
regards, tom lane
| From: | Gavin Sherry <swm(at)linuxworld(dot)com(dot)au> |
|---|---|
| To: | Karel Zak <zakkr(at)zf(dot)jcu(dot)cz> |
| Cc: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Memory management, palloc |
| Date: | 2001-03-08 15:19:14 |
| Message-ID: | Pine.LNX.4.21.0103090218390.11367-100000@linuxworld.com.au |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Lists: | pgsql-hackers |
Karel,
On Thu, 8 Mar 2001, Karel Zak wrote:
> On Thu, Mar 08, 2001 at 10:28:50PM +1100, Gavin Sherry wrote:
> > Hi guys,
> >
> > I've been looking through the memory management system today.
> >
> > When a request is made for a memory memory chunk larger than
> > ALLOC_CHUNK_LIMIT, AllocSetAlloc() uses malloc() to give the request its
> > own block. The result is tested by AllocSetAlloc() to see if the memory
> > was allocated.
> >
> > Irrespective of this, a chunk can be returned which has not had memory
> > allocated to it. There is no testing of the return status of
> > palloc() through out the code.
>
> I don't understand. If some memory is not obtain in AllocSetAlloc()
> all finish with elog(ERROR). Not exists way how return insufficient
> space. Or not?
Ahh. Of course. My mistake =)
Gavin