[PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: 回复: [PERFORM] PG as in-memory db? How to warm up and re-populate buffers? How to read in all tuples into memory?

2012-03-02 Thread Tomas Vondra
On 2.3.2012 03:05, Claudio Freire wrote: On Thu, Mar 1, 2012 at 10:13 PM, Tomas Vondra t...@fuzzy.cz wrote: Maybe. I still am not sure how fsync=off affects the eviction in your opinion. I think it does not (or just very remotely) and you were saying the opposite. IMHO the eviction of (dirty)

[PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: 回复: [PERFORM] PG as in-memory db? How to warm up and re-populate buffers? How to read in all tuples into memory?

2012-03-01 Thread Tomas Vondra
On 28.2.2012 17:42, Claudio Freire wrote: On Tue, Feb 28, 2012 at 1:05 PM, Tomas Vondra t...@fuzzy.cz wrote: On 28 Únor 2012, 15:24, Claudio Freire wrote: It speeds a lot more than the initial load of data. Assuming the database is read-only, but not the filesystem (ie: it's not a slave, in

[PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: 回复: [PERFORM] PG as in-memory db? How to warm up and re-populate buffers? How to read in all tuples into memory?

2012-03-01 Thread Claudio Freire
On Thu, Mar 1, 2012 at 10:13 PM, Tomas Vondra t...@fuzzy.cz wrote: Maybe. I still am not sure how fsync=off affects the eviction in your opinion. I think it does not (or just very remotely) and you were saying the opposite. IMHO the eviction of (dirty) buffers is either very fast or slow, no

[PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: 回复: [PERFORM] PG as in-memory db? How to warm up and re-populate buffers? How to read in all tuples into memory?

2012-02-28 Thread Tomas Vondra
On 28 Únor 2012, 15:24, Claudio Freire wrote: On Tue, Feb 28, 2012 at 11:15 AM, Tomas Vondra t...@fuzzy.cz wrote: I haven't investigated why exactly the data are not cached initially, but none of the options that I can think of could be fixed by setting fsync=off. That's something that

[PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: [PERFORM] Re: 回复: [PERFORM] PG as in-memory db? How to warm up and re-populate buffers? How to read in all tuples into memory?

2012-02-28 Thread Claudio Freire
On Tue, Feb 28, 2012 at 1:05 PM, Tomas Vondra t...@fuzzy.cz wrote: On 28 Únor 2012, 15:24, Claudio Freire wrote: It speeds a lot more than the initial load of data. Assuming the database is read-only, but not the filesystem (ie: it's not a slave, in which case all this is moot, as you said,