Hi All!

First, thanks for answers!

Richard Huxton wrote:

On Thursday 07 August 2003 09:24, Yaroslav Mazurak wrote:

IIRC there is a limit on filesystem cache on freeBSD. 300MB by default.
If that is the case, you might have to raise it to make
effective_cache_size really effective..

        "Try various sysctls" says nothing for me. I want use *all available
RAM* (of course, without needed for OS use) for PostgreSQL.

PG will be using the OS' disk caching.

I think all applications using OS disk caching. ;)
Or you want to say that PostgreSQL tuned for using OS-specific cache implementation?
Do you know method for examining real size of OS filesystem cache? If I understood right, PostgreSQL dynamically use all available RAM minus shared_buffers minus k * sort_mem minus effective_cache_size?
I want configure PostgreSQL for using _maximum_ of available RAM.

Looks fine - PG isn't growing too large and your swap usage seems steady. We can try upping the sort memory later, but given the amount of data you're dealing with I'd guess 64MB should be fine.

I think we're going to have to break the query down a little and see where the issue is.

What's the situation with:
EXPLAIN ANALYZE SELECT <some_field> FROM v_file02wide WHERE a011 = 3 AND inrepdate(data) AND b030 IN (SELECT b030 FROM dov_bank WHERE dov_bank_box_22(box) IN ('NL', 'NM')) AND r030 = 980;

EXPLAIN ANALYZE SELECT SUM(showcalc(<parameters>)) FROM <something simple>

Hopefully one of these will run in a reasonable time, and the other will not. Then we can examine the slow query in more detail. Nothing from your previous EXPLAIN (email of yesterday 13:42) looks unreasonable but something must be going wild in the heart of the query, otherwise you wouldn't be here.

Yes, you're right. I've tested a few statements and obtain interesting results.
SELECT * FROM v_file02wide WHERE... executes about 34 seconds.
SELECT showcalc(...); executes from 0.7 seconds (without recursion) up to 6.3 seconds if recursion is used! :(
This mean, that approximate execute time for fully qualified SELECT with about 8K rows is... about 13 hours! :-O
Hence, problem is in my function showcalc:

-- Parameters: code, dd, r020, t071
(SELECT sc.koef * $4
FROM showing AS s NATURAL JOIN showcomp AS sc
WHERE s.kod = $1
AND NOT SUBSTR(acc_mask, 1, 1) = ''[''
AND SUBSTR(acc_mask, 1, 4) = $3
AND SUBSTR(acc_mask, 5, 1) = SUBSTR($2, 1, 1)),
(SELECT SUM(sc.koef * COALESCE(showcalc(SUBSTR(acc_mask, 2, LENGTH(acc_mask) - 2), $2, $3, $4), 0))
FROM showing AS s NATURAL JOIN showcomp AS sc
WHERE s.kod = $1
AND SUBSTR(acc_mask, 1, 1) = ''[''),
0) AS showing;

BTW, cross join "," with WHERE clause don't improve performance relative to NATURAL JOIN.
Additionally, with user-defined function beginchar (SUBSTR(..., 1, 1)), used for indexing, showcalc executes about 16 seconds. With function SUBSTR the same showcalc executes 6 seconds.

Table showing contain information about showing: showing id (id_show), code (kod) and description (opys). Table showcomp contain information about showing components (accounts): showing id (id_show), coefficient (koef) and account_mask (acc_mask). Account mask is 4-char balance account mask || 1-char account characteristics or another showing in square bracket.
id_show | kod | opys
1 | 'A00101' | 'Received'
2 | 'A00102' | 'Sent'
3 | 'A00103' | 'Total'
id_show | koef | acc_mask
1 | 1.0 | '60102'
1 | 1.0 | '60112'
2 | 1.0 | '70011'
2 | 1.0 | '70021'
3 | 1.0 | '[A00101]'
3 | -1.0 | '[A00102]'
This mean that: A00101 includes accounts 6010 and 6011 with characteristics 2, A00102 includes accounts 7001 and 7002 with characteristics 1, and A00103 = A00102 - A00101. In almost all cases recursion depth not exceed 1 level, but I'm not sure. :)

View v_file02wide contain account (r020) and 2-char characteristics (dd). Using showcalc I want to sum numbers (t071) on accounts included in appropriate showings. I.e SELECT SUM(showcalc('A00101', dd, r020, t071)) FROM ... must return sum on accounts 6010 and 6011 with characteristics 2 etc.

Now I think about change function showcalc or/and this data structures... :)
Anyway, 600Mb is too low for PostgreSQL for executing my query - DBMS raise error after 11.5 hours (of estimated 13?). :(

With best regards Yaroslav Mazurak.

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