Hi Stefan About "prepare statements calls/traces ", in paralell select count(*), this service that insert in 10 and 10 minutes. But even without such active service , the time is the same, 90 minutes. My mistake, my server have 6 cores. Hi, (as a side note, I'm afraid I'm too "old fashioned" and do no longer understand "modern" MonetDB traces; at least, I have no idea, why there are so many prepare statements calls/traces in your trace of a simple select count(*) query ... ) Having said that, the trace suggests that your machine either has 6 cores, or MonetDB has decided to split it in 6 slices for processing, although you machine has only 4 cores? Also, the trace reveals that the vast majority of the time is spent in 6 (one per slice) sql.tid() calls: ....... -- Luciano Sasso Vieira Data Scientist & Solutions Architect luciano@gsgroup.com.br http://www.gsgroup.com.br | tel: 17 3353-0833 | cel: 17 99706-9335 www.gsgroup.com.br http://www.gsgroup.com.br --- Este email foi escaneado pelo Avast antivírus. https://www.avast.com/antivirus