Examples of org.chaidb.db.index.btree.bufmgr.PageBufferManager

Package org.chaidb.db.index.btree.bufmgr

Examples of org.chaidb.db.index.btree.bufmgr.PageBufferManager

org.chaidb.db.index.btree.bufmgr.PageBufferManager
This class manages a buffer to cache certain amount of pages. It keeps a buffered page pool using byte[][], a hashtable matches pageNumber to page information, a look aside link list keeps all the pages not accessed by any thread at the moment.
If a thread trying to fetch a page, it gets the page info from the hashtable first.
If the page info indicated the page is a fixed page, which means it is accessed by some thread at the moment, the page is directly returned.
If the page is in a look aside link list, the page is removed from there, and becomes fixed page, and return.
If the page is not found, read it from pagedFile, put as fixed.
If there is no slot in the buffer for a new page, the first node (header) in the look aside link list is kicked off. If it is dirty, will do a write through.

After finishing reading / writing, insert the page to the end of look aside link list.
@version 1.0


        if (nextNodePos == null) {
            nextNodePos = nodePos;
        }


        final PageBufferManager buffer = btree.getBuffer();
        final BTreeSpec btreeSpec = btree.getBTreeSpec();
        PageNumber dupPageNumber = new PageNumber(nodePos.getPageNo());
        try {
            DataPage curDataPage = new DataPage(btree.getBtreeId(), dupPageNumber, btreeSpec, buffer);
            DataNode curDataNode = new DataNode(curDataPage, nodePos.getOffsetInPage());
            curDataNode.setFlags(BTreeSpec.DATA_NODE_DUP_NEXT);
            byte[] oldData = ByteTool.copyByteArray(curDataNode.getPage().getPage(), curDataNode.getNodeOffset(), (int) curDataNode.getNodeSpace());
            byte[] data = new byte[8];
            ByteTool.intToBytes(data, 0, nextNodePos.getOffsetInPage());
            ByteTool.intToBytes(data, 4, nextNodePos.getPageNo());
            curDataNode.storeNode(data, oldData, kContext);
            buffer.releasePage(btree.getBtreeId(), nodePos.getPageNo(), true);
        } catch (ChaiDBException e) {
            logger.error(e);
            buffer.releasePage(btree.getBtreeId(), nodePos.getPageNo(), false);
        }
    }

View Full Code Here

        }


        int nPageNo = bulkNextNodePos.getPageNo();


        int id = btree.getBtreeId();
        final PageBufferManager buffer = btree.getBuffer();
        final BTreeSpec btreeSpec = btree.getBTreeSpec();
        PageNumber dupPageNumber = new PageNumber(nPageNo);


        try {
            DataPage dupDataPage = new DataPage(id, dupPageNumber, btreeSpec, buffer);
            int pageCount = 0;
            while (pageCount < page && !finished) {
                NodeInfo node = new NodeInfo();
                node.nodePosition = bulkNextNodePos;
                int ret = getNode(dupDataPage, node);
                bulkNextNodePos = node.nodeNextPosition;
                if ((ret & DUP_FINISHED) == DUP_FINISHED) {
                    finished = true;
                    if ((ret & DUP_NEXT) == DUP_NEXT) {
                        break;
                    }
                }
                if ((ret & DUP_DATA) == DUP_DATA) {
                    cache.add(node);
                } else if ((ret & DUP_NEXT) == DUP_NEXT) {
                    if (bulkNextNodePos.getPageNo() == nPageNo) {
                        continue;
                    } else {
                        if (cache.size() > 0) {
                            pageCount++;
                        }
                        if (pageCount < page) {
                            nPageNo = bulkNextNodePos.getPageNo();
                            buffer.releasePage(id, dupPageNumber, false);
                            dupPageNumber = new PageNumber(nPageNo);
                            dupDataPage = new DataPage(id, dupPageNumber, btreeSpec, buffer);
                        }
                    }
                } else {
                    logger.error("Failed to get next dup node.");
                }
            }
        } catch (ChaiDBException e) {
            logger.error(e);
        } finally {
            buffer.releasePage(id, dupPageNumber, false);
        }
        return Collections.unmodifiableList(cache);
    }

View Full Code Here

    protected NodeInfo getNextDataNode(NodePosition nodePos) {
        if (finished) {
            return null;
        }
        int id = btree.getBtreeId();
        final PageBufferManager buffer = btree.getBuffer();
        final BTreeSpec btreeSpec = btree.getBTreeSpec();
        dupNextCountForTest = dupNextCountForNextNode;
        dupNextCountForNextNode = 0;


        int curPageNo = nodePos.getPageNo();
        PageNumber dupPageNumber = new PageNumber(curPageNo);
        try {
            DataPage dupDataPage = new DataPage(id, dupPageNumber, btreeSpec, buffer);
            NodeInfo node = new NodeInfo();
            node.nodePosition = nodePos;
            while (true) {
                int ret = getNode(dupDataPage, node);
                if ((ret & DUP_FINISHED) == DUP_FINISHED) {
                    finished = true;
                    if ((ret & DUP_NEXT) == DUP_NEXT) {
                        break;
                    }
                }
                if ((ret & DUP_DATA) == DUP_DATA) {
                    return node;
                } else if ((ret & DUP_NEXT) == DUP_NEXT) {
                    node.nodePosition = node.nodeNextPosition;
                    if (node.nodeNextPosition.getPageNo() != curPageNo) {
                        curPageNo = node.nodeNextPosition.getPageNo();
                        buffer.releasePage(id, dupPageNumber, false);
                        dupPageNumber = new PageNumber(curPageNo);
                        dupDataPage = new DataPage(id, dupPageNumber, btreeSpec, buffer);
                    }
                } else {
                    logger.error("Failed to get next dup node.");
                    break;
                }
            }
        } catch (ChaiDBException e) {
            logger.error(e);
        } finally {
            buffer.releasePage(id, dupPageNumber, false);
        }


        return null;
    }

View Full Code Here

        byte[] data = null;
        try {
            //lock the page pointed by this node
            DataPage dataPage = new DataPage(page.getBtreeSpec().btree.getBtreeId(), pageNumber, page.getBtreeSpec(), page.getBuffer());
            data = new DataNode(dataPage, dataNodeOffset).getData();
            PageBufferManager buffer = page.getBuffer();
            buffer.releasePage(pageNumber.getTreeId(), pageNumber, false);
            return data;
        } catch (ChaiDBException e) {
            String details = page.pageNumber.toHexString() + " of " + page.getBtreeSpec().btree.getBTreeName();
            logger.error(details);
            throw e;

View Full Code Here

     *         update date:2001-10-12 by marriane,delete freelist recover
     */
    protected boolean doRedo(byte[] page) throws ChaiDBException {
        try {
            /* add page to freelist of BufferedPage in memory*/
            PageBufferManager bp = bpm;
            bp.addToFreeList(treeId, super.getPageNum(), new Integer(super.getTxnId()));


            if (DataPage.isNormalDataPage((int) pageFlag)) {
                bp.removeLatestDataPage(docid, treeId, super.getPageNum(), new Integer(super.getTxnId()));
            }


            return true;
        } catch (Exception e) {
            logger.debug(e);

View Full Code Here

     * redo
     *
     * @return boolean true|false
     */
    protected boolean doRedo() throws ChaiDBException {
        PageBufferManager bp = bpm;
        return bp.updateBTreeSpec(treeId, newPageNum, flag, new Integer(super.getTxnId()), docIdArr, this.btreeType);


    }

View Full Code Here

                /* needn't do undo while flag is NODE_SIZE_FLAG, because
                it is not meaning. ?!*/
                flag == NODE_SIZE_FLAG) //appended by ben at Aug, 06, 2002
            return false;


        PageBufferManager bp = bpm;
        return bp.updateBTreeSpec(treeId, oldPageNum, flag, new Integer(super.getTxnId()), docIdArr, this.btreeType);
    }

View Full Code Here

     * Get a page specified by this log record.
     *
     * @return page,if sucess. Otherwise, null.
     */
    protected byte[] getPage(int newPageNum, boolean redo) throws ChaiDBException {
        PageBufferManager bp = bpm;
        byte[] page = bp.getPage(super.getTxnId(), treeId, btreeType, newPageNum, redo, locks);
        return page;
    }

View Full Code Here

    protected boolean doRedo(byte[] page) throws ChaiDBException {
        /* redo allocate a new page function */
        /* free the allocated page function */
        try {
            /* add page to freelist of BufferedPage in memory*/
            PageBufferManager bp = bpm;
            bp.addToFreeList(treeId, super.getPageNum(), new Integer(super.getTxnId()));


            if (DataPage.isNormalDataPage((int) pageFlag)) {
                bp.removeLatestDataPage(docid, treeId, super.getPageNum(), new Integer(super.getTxnId()));
            }
            return true;
        } catch (Exception e) {
            logger.debug(e);
            throw new ChaiDBException(ErrorCode.LOG_REDO_FAILED, e.toString());

View Full Code Here

            /* set metadata's lowbound and uppbound data with default value */
            System.arraycopy(ByteTool.shortToBytes((short) BTreeSpec.PAGE_HEADER_SIZE), 0, page, BTreeSpec.OFF_LOWERBOUND, 2);
            System.arraycopy(ByteTool.shortToBytes((short) BTreeSpec.PAGE_SIZE), 0, page, BTreeSpec.OFF_UPPERBOUND, 2);


            /* add page to freelist of BufferedPage in memory*/
            PageBufferManager bp = bpm;
            bp.addToFreeList(treeId, super.getPageNum(), new Integer(super.getTxnId()));


            if (isDataPage(pageFlag))
                bp.removeLatestDataPage(docId, treeId, super.getPageNum(), new Integer(super.getTxnId()));


            //add 1 on the free page number in metadata page of file if it's not in freelist
        } catch (Exception e) {
            logger.debug(e);
            throw new ChaiDBException(ErrorCode.LOG_UNDO_FAILED, e.toString());

View Full Code Here

0 1

TOP

Related Classes of org.chaidb.db.index.btree.bufmgr.PageBufferManager

org.chaidb.db.helper.AbstractDaemonThread

org.chaidb.db.helper.cache.storage.BTreePathStorage

org.chaidb.db.index.btree.BTreeNode

org.chaidb.db.index.btree.hbt.HyperBTreeBasicIterator

org.chaidb.db.index.btree.hbt.HyperBTreeCachedIterator

org.chaidb.db.index.btree.hbt.HyperBTreeIterator

org.chaidb.db.index.IDBIndex

org.chaidb.db.log.logrecord.BTreeFreeOverflowPageLogRecord

org.chaidb.db.log.logrecord.BTreeFreePageLogRecord

org.chaidb.db.log.logrecord.BTreeFreePageWithDataLogRecord

All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.