addCompletion() public method

public addCompletion ( handleWriteGroupCompletion fn ) : void
fn handleWriteGroupCompletion
return void
Exemplo n.º 1
0
        public void freeSegment(LayerWriteGroup tx, FreespaceExtent segment_extent)
        {
            // (1) add the segment to the pending list (pending free)

            if (tx.type != LayerWriteGroup.WriteGroupType.DISK_ATOMIC_FLUSH) {
                throw new Exception("freeSegment() requires DISK_ATOMIC write group");
            }

            // NOTE: DISK_ATOMIC writes are not seen in the memory segment until the atomic write group applies
            //       so these changes will not be seen until then

            RecordKey key = new RecordKey().appendParsedKey(".ROOT/FREELIST/PENDING")
                .appendKeyPart(new RecordKeyType_Long(segment_extent.end_addr));

            RecordUpdate payload = RecordUpdate.WithPayload(segment_extent.pack());
            tx.setValue(key, payload);

            // (2) add a handler to get notified when the block is no longer referenced, so it can
            //     be moved from pending to actually free.

            LayerWriteGroup fwg = this.store.newWriteGroup(LayerWriteGroup.WriteGroupType.DISK_ATOMIC_NOFLUSH);

            // we don't want to ask for the notification until the write-group freeing this segment is finished
            tx.addCompletion(delegate() {
                tx.mylayer.regionmgr.notifyRegionSafeToFree(segment_extent.start_addr,
                    delegate(long addr) { this.handleRegionSafeToFree(addr, segment_extent, fwg); });
            });
        }