Summary information |
|
|---|---|
Default value |
2 |
Range of values |
0–31 |
Status |
Dynamic |
Display level |
Comprehensive |
Required role |
System Administrator |
number of pre-allocated extents specifies the number of extents (eight pages) allocated in a single trip to the page manager. Currently, it is used only by bcp to improve performance when copying in large amounts of data. By default, bcp allocates two extents at a time and writes an allocation record to the log each time.
Setting number of pre-allocated extents means that bcp allocates the specified number of extents each time it requires more space, and writes a single log record for the event. Setting the value to 0 disables extent allocation so that a single page is allocated each time bulk copy needs a page. Since each page allocation is logged, this can greatly increase the amount of transaction log space required.
An object may be allocated more pages than actually needed, so the value of number of pre-allocated extents should be low if you are using bcp for small batches. If you are using bcp for large batches, increase the value of number of pre-allocated extents to reduce the amount of overhead required to allocate pages and to reduce the number of log records.
