| Subject | Re: UPDATE to same record causing heavy disk I/O |
|---|---|
| Author | Dmitry Yemanov |
| Post date | 2015-12-24T18:03:33Z |
24.12.2015 05:31, 'Leyne, Sean' wrote:
for the same data = slower performance. Situation is better for SSDs,
but "silly-low cost" does not really apply there.
Dmitry
>It's not about storage cost, but about IOPS. Bigger record = more I/O
> With today's unlimited availability of disk space and silly-low cost per GB for storage, would an argument to dispense with the delta and simply store a full copy of the record (not including BLOB) be worthy of discussion?
for the same data = slower performance. Situation is better for SSDs,
but "silly-low cost" does not really apply there.
> I know that Jim has mentioned that in his later db engine he has adopted a reverse approach which has the latest version stored in full and for transactions required back versions responsible processing the deltas. In this way, the latest version of the row are always complete so that the back versions can be dropped very efficiently.Isn't it exactly how Firebird works?
Dmitry