AW: Storage Manager (was postgres 7.2 features.)

From: Zeugswetter Andreas SB <ZeugswetterA(at)wien(dot)spardat(dot)at>
To: "'Jan Wieck'" <JanWieck(at)Yahoo(dot)com>, PostgreSQL HACKERS <pgsql-hackers(at)postgresql(dot)org>
Subject: AW: Storage Manager (was postgres 7.2 features.)
Date: 2000-07-11 14:09:18
Message-ID: 11C1E6749A55D411A9670001FA687963367FF2@sdexcsrv1.f000.d0188.sd.spardat.at
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers


> > * It's always faster than WAL in the presence of stable main memory.
> > (Whether the stable caches in modern disk drives is an
> approximation I
> > don't know).
>
> For writing, yes. But for high updated tables, the scans will
> soon slow down due to the junk contention.

Can you elaborate please ? If we centralized writes, then the
non-overwrite smgr would be very efficient since it only writes to the end
of a table (e.g. one page write for pagesize/rowsize rows).

>
> > * It's more scalable and has less logging contention. This allows
> > greater scalablility in the presence of multiple processors.
> >
> > * Instantaneous crash recovery.
>
> Because this never worked reliable, Vadim is working on WAL

crash recovery is bullet proof. the WAL is only needed for rollforward
after restore with our non overwrite smgr.
I do agree that we need a txlog.

Andreas

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Zeugswetter Andreas SB 2000-07-11 14:17:02 AW: update on TOAST status'
Previous Message Michael J Schout 2000-07-11 14:07:20 Re: Re: postgres TODO