Monetdb copy binary time varys very much!
hlfwmqd at gmail.com
Fri Jul 26 16:11:43 CEST 2013
I follow you advise, and there is error as follows:
ERROR = !COPY INTO: cannot pass number of records when using binary COPY
INTO in: "copy 200000 records binary into tmatch
!current transaction is aborted (please ROLLBACK)
2013/7/26 Martin Kersten <Martin.Kersten at cwi.nl>
> This runs shows expected flushing.
> You might get somewhat better performance when you follow
> the advice in http://www.monetdb.org/**Documentation/Cookbooks/**
> e.g. use COPY 44000000 RECORDS ....
> The COPY INTO forms mentioned so far share one important drawback. When a
> lot of data is to be inserted, the server doesn't know how much memory to
> allocate for the tables, and so will likely allocate too little. This means
> that during the insertion process, the server has to grow the allocated
> memory area. This can be an expensive operation. Therefore, it is better
> to give the server a count of how many records are to be inserted:
> COPY n RECORDS INTO table FROM 'file';
> Here n should be a number that is at least as large as the actual number
> of records to be inserted. If the file contains more than n records, only
> n will be inserted, if the file contains fewer, all values will be
> inserted. Giving a higher number is especially useful if multiple COPY
> INTO queries are to be done on the same table. The first COPY INTO, when
> the table is still empty, should be the total count of to-be-inserted
> values so that the server will allocate enough memory when the tables are
> first created (they are only really created once data is inserted).
> On 7/26/13 10:58 AM, integrity wrote:
>> ------------------ Original ------------------
>> *From: * "Martin Kersten"<Martin.Kersten at cwi.nl**>;
>> *Date: * Fri, Jul 26, 2013 04:46 PM
>> *To: * "users-list"<users-list@**monetdb.org <users-list at monetdb.org>>;
>> *Subject: * Re: Monetdb copy binary time varys very much!
>> You should plot the times of each of your runs to see the trend.
>> This single run may be an outlier, which could come from anything
>> in your system environment. Even a seemingly harmless concurrent
>> program using significant memory could compete with MonetDB.
>> And indeed, at some point you will see disk IO.
>> regards, Martin
>> users-list mailing list
>> users-list at monetdb.org
> users-list mailing list
> users-list at monetdb.org
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