Thanx Stefan! Version is MonetDB/XQyert Stable 0.22 (using default backend). So the remaining time would be "client/server communication"??? That is an awful lot. The query is a reporting query, i.e., the query has many aggregates calculating all kinds of statistics and then creates XHTML structures for the resulting tables. The resulting XHTML-data is not so large that it would eat up 18.9 seconds. Aren't there any other aspects that may be involved here? Maurice. Stefan Manegold wrote:
On Tue, Mar 25, 2008 at 09:12:44AM +0100, Keulen, M. van (Maurice) wrote:
Hi,
A student of mine is trying to speed up some queries and is puzzled about the timing-readings he gets, for example:
Trans 19681.811 msec: Query translation ("compilation") (server) Shred 0.000 msec: Document shredding & loading (server) Query 16384.143 msec: Query execution (server) Print 81.180 msec: Result serialization (server) Timer 55087.438 msec: Wallclock (client; all above + client-server communication)
The total of the first four 19.7+0+16.4+0.08 is approximately 36.2 seconds. "Timer" gives 55.1 seconds. Where are the remaining 18.9 seconds going?
(unless there is a bug somewhere:) "client-server communication" (cf., http://www.cwi.nl/htbin/ins1/publications?request=abstract&key=Ma:TR-CWI:07)
Which version of MonetDB/XQuery are we talking about?
By the way, what do these measures precisely indicate? "Query", for example, can be interpreted as query compilation or query execution.
See above.
Stefan
Maurice.
-- ---------------------------------------------------------------------- Dr.Ir. M. van Keulen - Assistant Professor, Data Management Technology Univ. of Twente, Dept of EEMCS, POBox 217, 7500 AE Enschede, Netherlands Email: m.vankeulen@utwente.nl, Phone: +31 534893688, Fax: +31 534892927 Room: ZI 3039, WWW: http://www.cs.utwente.nl/~keulen