Summary
tuning feature: configures the minimum size of free space slots in the database file
that are to be reused.
- Assembly
- Db4objects
.Db4o-2010 .dll - Namespace
- Db4objects
.Db4o .Config - Containing Type
- I
Freespace Configuration
Syntax
void DiscardSmallerThan(int byteCount)Remarks
tuning feature: configures the minimum size of free space slots in the database file
that are to be reused.
When objects are updated or deleted, the space previously occupied in the database file is marked as "free", so it can be reused. db4o maintains two lists in RAM, sorted by address and by size. Adjacent entries are merged. After a large number of updates or deletes have been executed, the lists can become large, causing RAM consumption and performance loss for maintenance. With this method you can specify an upper bound for the byte slot size to discard.
Pass Integer.MAX_VALUE to this method to discard all free slots for the best possible startup time.
The downside of setting this value: Database files will necessarily grow faster.
Default value:
0 all space is reused
When objects are updated or deleted, the space previously occupied in the database file is marked as "free", so it can be reused. db4o maintains two lists in RAM, sorted by address and by size. Adjacent entries are merged. After a large number of updates or deletes have been executed, the lists can become large, causing RAM consumption and performance loss for maintenance. With this method you can specify an upper bound for the byte slot size to discard.
Pass Integer.MAX_VALUE to this method to discard all free slots for the best possible startup time.
The downside of setting this value: Database files will necessarily grow faster.
Default value:
0 all space is reused
Parameters
| Name | Type | Description |
|---|---|---|
| byteCount | int | Slots with this size or smaller will be lost. |
Return Value
| Type | Description |
|---|---|
| void |