After plenty of querys the database use 40 times more disk space than the original data, How can I avoid this?
Hi guys: In my case , original data 8G bytes, but after plenty of query, the disk space usage is 361G bytes. The query is simply, first five UNION ALL, then fetch the result. When the query is running, I use vmstat to watch the IO status. When the database becomes larger, the BI and BO number increase very large too, for example bo 355224, bi 27392. And the query cost ten times longer than before! After rebooting the database, the database disk space was reduced to its original data size, 8G. It seems too much runtime data was produced. How can I solve the problem or avoid the problem! Thanks,Jason ****************************************************************************************** This email and its attachments contain confidential information from HUAWEI, which is intended only for the person or entity whose address is listed above. Any use of the information contained here in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this email in error, please notify the sender by phone or email immediately and delete it! *****************************************************************************************
Hi Jason, to be able to analyze the problem, we'd need all the information to be able to reproduce it; this includes at least - exact version of MonetDB - operating system - hardware, in particular #hardware threads and size of RAM (the output of `mserver5 --version` should contain all these) - database schema and queries - data; or at least EXPLAIN's and TRACE's of your queries Preferably, file a bug report with all this information. Best, Stefan ----- Original Message -----
Hi guys: In my case , original data 8G bytes, but after plenty of query, the disk space usage is 361G bytes. The query is simply, first five UNION ALL, then fetch the result. When the query is running, I use vmstat to watch the IO status. When the database becomes larger, the BI and BO number increase very large too, for example bo 355224, bi 27392. And the query cost ten times longer than before! After rebooting the database, the database disk space was reduced to its original data size, 8G. It seems too much runtime data was produced. How can I solve the problem or avoid the problem!
Thanks,Jason
****************************************************************************************** This email and its attachments contain confidential information from HUAWEI, which is intended only for the person or entity whose address is listed above. Any use of the information contained here in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this email in error, please notify the sender by phone or email immediately and delete it! ***************************************************************************************** _______________________________________________ developers-list mailing list developers-list@monetdb.org http://mail.monetdb.org/mailman/listinfo/developers-list
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