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Posted to commits@bookkeeper.apache.org by si...@apache.org on 2017/08/11 10:11:46 UTC
[bookkeeper] 09/10: ISSUE #356: Release notes 4.5.0
This is an automated email from the ASF dual-hosted git repository.
sijie pushed a commit to branch branch-4.5
in repository https://gitbox.apache.org/repos/asf/bookkeeper.git
commit 06178108f4995775f0c7744991c0882119e00d37
Author: Sijie Guo <si...@apache.org>
AuthorDate: Thu Aug 10 13:28:33 2017 -0700
ISSUE #356: Release notes 4.5.0
Descriptions of the changes in this PR:
- summary for release 4.5.0
- highlights for 4.5.0
- full list of JIRA and Github issues.
Author: Sijie Guo <si...@apache.org>
Reviewers: Enrico Olivelli <eo...@gmail.com>, Jia Zhai <None>, Matteo Merli <mm...@apache.org>, Venkateswararao Jujjuri (JV) <None>
This closes #402 from sijie/release_notes_4.5.0, closes #356
---
site/docs/4.5.0/overview/releaseNotes.md | 500 ++++++++++++++++++++++++++++++-
site/releases.md | 10 +-
2 files changed, 504 insertions(+), 6 deletions(-)
diff --git a/site/docs/4.5.0/overview/releaseNotes.md b/site/docs/4.5.0/overview/releaseNotes.md
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--- a/site/docs/4.5.0/overview/releaseNotes.md
+++ b/site/docs/4.5.0/overview/releaseNotes.md
@@ -2,16 +2,508 @@
title: Apache BookKeeper 4.5.0 Release Notes
---
-[provide a summary of this release]
+This is the fifth release of BookKeeper as an Apache Top Level Project!
+
+The 4.5.0 release incorporates hundreds of new fixes, improvements, and features since previous major release, 4.4.0,
+which was released over a year ago. It is a big milestone in Apache BookKeeper community, converging from three
+main branches (Salesforce, Twitter and Yahoo).
Apache BookKeeper users are encouraged to upgrade to 4.5.0. The technical details of this release are summarized
below.
## Highlights
-[List the highlights]
+The main features in 4.5.0 cover are around following areas:
+
+- Dependencies Upgrade
+- Security
+- Public API
+- Performance
+- Operations
+
+### Dependencies Upgrade
+
+Here is a list of dependencies upgraded in 4.5.0:
+
+- Moved the developement from Java 7 to Java 8.
+- Upgrade Protobuf to `2.6`.
+- Upgrade ZooKeeper from `3.4` to `3.5`.
+- Upgrade Netty to `4.1`.
+- Upgrade Guava to `20.0`.
+- Upgrade SLF4J to `1.7.25`.
+- Upgrade Codahale to `3.1.0`.
+
+### Security
+
+Prior to this release, Apache BookKeeper only supports simple `DIGEST-MD5` type authentication.
+
+With this release of Apache BookKeeper, a number of feature are introduced that can be used, together of separately,
+to secure a BookKeeper cluster.
+
+The following security features are currently supported.
+
+- Authentication of connections to bookies from clients, using either `TLS` or `SASL (Kerberos).
+- Authentication of connections from clients, bookies, autorecovery daemons to `ZooKeeper`, when using zookeeper
+ based ledger managers.
+- Encryption of data transferred between bookies and clients, between bookies and autorecovery daemons using `TLS`.
+
+It's worth noting that those security features are optional - non-secured clusters are supported, as well as a mix
+of authenticated, unauthenticated, encrypted and non-encrypted clients.
+
+For more details, have a look at [BookKeeper Security](../../security/overview).
+
+### Public API
+
+There are multiple new client features introduced in 4.5.0.
+
+#### LedgerHandleAdv
+
+The [Ledger API] is the low level API provides by BookKeeper for interacting with `ledgers` in a bookkeeper cluster.
+It is simple but not flexible on ledger id or entry id generation. Apache BookKeeper introduces `LedgerHandleAdv`
+as an extension of existing `LedgerHandle` for advanced usage. The new `LedgerHandleAdv` allows applications providing
+its own `ledger-id` and assigning `entry-id` on adding entries.
+
+See [Ledger Advanced API](../../api/ledger-adv-api) for more details.
+
+#### Long Poll
+
+`Long Poll` is a main feature that [DistributedLog](https://distributedlog.io) uses to achieve low-latency tailing.
+This big feature has been merged back in 4.5.0 and available to BookKeeper users.
+
+This feature includes two main changes, one is `LastAddConfirmed` piggyback, while the other one is a new `long poll` read API.
+
+The first change piggyback the latest `LastAddConfirm` along with the read response, so your `LastAddConfirmed` will be automatically advanced
+when your read traffic continues. It significantly reduces the traffic to explicitly polling `LastAddConfirmed` and hence reduces the end-to-end latency.
+
+The second change provides a new `long poll` read API, allowing tailing-reads without polling `LastAddConfirmed` everytime after readers exhaust known entries.
+Although `long poll` API brings great latency improvements on tailing reads, it is still a very low-level primitive.
+It is still recommended to use high level API (e.g. [DistributedLog API](../../api/distributedlog-api)) for tailing and streaming use cases.
+
+See [Streaming Reads](https://distributedlog.incubator.apache.org/docs/latest/user_guide/design/main.html#streaming-reads) for more details.
+
+#### Explicit LAC
+
+Prior to 4.5.0, the `LAC` is only advanced when subsequent entries are added. If there is no subsequent entries added,
+the last entry written will not be visible to readers until the ledger is closed. High-level client (e.g. DistributedLog) or applications
+has to work around this by writing some sort of `control records` to advance `LAC`.
+
+In 4.5.0, a new `explicit lac` feature is introduced to periodically advance `LAC` if there are not subsequent entries added. This feature
+can be enabled by setting `explicitLacInterval` to a positive value.
+
+### Performance
+
+There are a lot for performance related bug fixes and improvements in 4.5.0. These changes includes:
+
+- Upgraded netty from 3.x to 4.x to leverage buffer pooling and reduce memory copies.
+- Moved developement from Java 7 to Java 8 to take advantage of Java 8 features.
+- A lot of improvements around scheduling and threading on `bookies`.
+- Delay ensemble change to improve tail latency.
+- Parallel ledger recovery to improve the recovery speed.
+- ...
+
+We outlined following four changes as below. For a complete list of performance improvements, please checkout the `full list of changes` at the end.
+
+#### Netty 4 Upgrade
+
+The major performance improvement introduced in 4.5.0, is upgrading netty from 3.x to [4.x](http://netty.io/wiki/new-and-noteworthy-in-4.0.html).
+
+For more details, please read [upgrade guide](../../admin/upgrade) about the netty related tips when upgrading bookkeeper from 4.4.0 to 4.5.0.
+
+#### Delay Ensemble Change
+
+`Ensemble Change` is a feature that Apache BookKeeper uses to achieve high availability. However it is an expensive metadata operation.
+Especially when Apache BookKeeper is deployed in a multiple data-centers environment, losing a data center will cause churn of metadata
+operations due to ensemble changes. `Delay Ensemble Change` is introduced in 4.5.0 to overcome this problem. Enabling this feature means
+an `Ensemble Change` will only occur when clients can't receive enough valid responses to satisfy `ack-quorum` constraint. This feature
+improves the tail latency.
+
+To enable this feature, please set `delayEnsembleChange` to `true` on your clients.
+
+#### Parallel Ledger Recovery
+
+BookKeeper clients recovers entries one-by-one during ledger recovery. If a ledger has very large volumn of traffic, it will have
+large number of entries to recover when client failures occur. BookKeeper introduces `parallel ledger recovery` in 4.5.0 to allow
+batch recovery to improve ledger recovery speed.
+
+To enable this feature, please set `enableParallelRecoveryRead` to `true` on your clients. You can also set `recoveryReadBatchSize`
+to control the batch size of recovery read.
+
+#### Multiple Journals
+
+Prior to 4.5.0, bookies are only allowed to configure one journal device. If you want to have high write bandwidth, you can raid multiple
+disks into one device and mount that device for jouranl directory. However because there is only one journal thread, this approach doesn't
+actually improve the write bandwidth.
+
+BookKeeper introduces multiple journal directories support in 4.5.0. Users can configure multiple devices for journal directories.
+
+To enable this feature, please use `journalDirectories` rather than `journalDirectory`.
+
+### Operations
+
+#### LongHierarchicalLedgerManager
+
+Apache BookKeeper supports pluggable metadata store. By default, it uses Apache ZooKeeper as its metadata store. Among the zookeeper-based
+ledger manager implementations, `HierarchicalLedgerManager` is the most popular and widely adopted ledger manager. However it has a major
+limitation, which it assumes `ledger-id` is a 32-bits integer. It limits the number of ledgers to `2^32`.
+
+`LongHierarchicalLedgerManager` is introduced to overcome this limitation.
+
+See [Ledger Manager](../../getting-started/concepts/#ledger-manager) for more details.
+
+#### Weight-based placement policy
+
+`Rack-Aware` and `Region-Aware` placement polices are the two available placement policies in BookKeeper client. It places ensembles based
+on users' configured network topology. However they both assume that all nodes are equal. `weight-based` placement is introduced in 4.5.0 to
+improve the existing placement polices. `weight-based` placement was not built as separated polices. It is built in the existing placement policies.
+If you are using `Rack-Aware` or `Region-Aware`, you can simply enable `weight-based` placement by setting `diskWeightBasedPlacementEnabled` to `true`.
+
+#### Customized Ledger Metadata
+
+A `Map<String, byte[]>` is introduced in ledger metadata in 4.5.0. Clients now are allowed to pass in a key/value map when creating ledgers.
+This customized ledger metadata can be later on used by user defined placement policy. This extends the flexibility of bookkeeper API.
+
+#### Add Prometheus stats provider
+
+A new [Prometheus](https://prometheus.io/) [stats provider](https://github.com/apache/bookkeeper/tree/master/bookkeeper-stats-providers/prometheus-metrics-provider)
+is introduce in 4.5.0. It simplies the metric collection when running bookkeeper on [kubernetes](https://kubernetes.io/).
+
+#### Add more tools in BookieShell
+
+`BookieShell` is the tool provided by Apache BooKeeper to operate clusters. There are multiple importants tools introduced in 4.5.0, for example, `decommissionbookie`,
+`expandstorage`, `lostbookierecoverydelay`, `triggeraudit`.
+
+For the complete list of commands in `BookieShell`, please read [BookKeeper CLI tool reference](../../reference/cli).
+
+## Full list of changes
+
+### JIRA
-## Details
+#### Sub-task
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-552'>BOOKKEEPER-552</a>] - 64 Bits Ledger ID Generation
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-553'>BOOKKEEPER-553</a>] - New LedgerManager for 64 Bits Ledger ID Management in ZooKeeper
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-588'>BOOKKEEPER-588</a>] - SSL support
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-873'>BOOKKEEPER-873</a>] - Enhance CreatedLedger API to accept ledgerId as input
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-949'>BOOKKEEPER-949</a>] - Allow entryLog creation even when bookie is in RO mode for compaction
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-965'>BOOKKEEPER-965</a>] - Long Poll: Changes to the Write Path
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-997'>BOOKKEEPER-997</a>] - Wire protocol change for supporting long poll
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1017'>BOOKKEEPER-1017</a>] - Create documentation for ZooKeeper ACLs
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1086'>BOOKKEEPER-1086</a>] - Ledger Recovery - Refactor PendingReadOp
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1087'>BOOKKEEPER-1087</a>] - Ledger Recovery - Add a parallel reading request in PendingReadOp
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1088'>BOOKKEEPER-1088</a>] - Ledger Recovery - Add a ReadEntryListener to callback on individual request
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1089'>BOOKKEEPER-1089</a>] - Ledger Recovery - allow batch reads in ledger recovery
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1092'>BOOKKEEPER-1092</a>] - Ledger Recovery - Add Test Case for Parallel Ledger Recovery
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1093'>BOOKKEEPER-1093</a>] - Piggyback LAC on ReadResponse
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1094'>BOOKKEEPER-1094</a>] - Long Poll - Server and Client Side Changes
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1095'>BOOKKEEPER-1095</a>] - Long Poll - Client side changes
+</li>
+</ul>
+
+#### Bug
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-852'>BOOKKEEPER-852</a>] - Release LedgerDescriptor and master-key objects when not used anymore
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-903'>BOOKKEEPER-903</a>] - MetaFormat BookieShell Command is not deleting UnderReplicatedLedgers list from the ZooKeeper
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-907'>BOOKKEEPER-907</a>] - for ReadLedgerEntriesCmd, EntryFormatter should be configurable and HexDumpEntryFormatter should be one of them
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-908'>BOOKKEEPER-908</a>] - Case to handle BKLedgerExistException
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-924'>BOOKKEEPER-924</a>] - addEntry() is susceptible to spurious wakeups
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-927'>BOOKKEEPER-927</a>] - Extend BOOKKEEPER-886 to LedgerHandleAdv too (BOOKKEEPER-886: Allow to disable ledgers operation throttling)
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-933'>BOOKKEEPER-933</a>] - ClientConfiguration always inherits System properties
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-938'>BOOKKEEPER-938</a>] - LedgerOpenOp should use digestType from metadata
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-939'>BOOKKEEPER-939</a>] - Fix typo in bk-merge-pr.py
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-940'>BOOKKEEPER-940</a>] - Fix findbugs warnings after bumping to java 8
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-952'>BOOKKEEPER-952</a>] - Fix RegionAwarePlacementPolicy
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-955'>BOOKKEEPER-955</a>] - in BookKeeperAdmin listLedgers method currentRange variable is not getting updated to next iterator when it has run out of elements
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-956'>BOOKKEEPER-956</a>] - HierarchicalLedgerManager doesn't work for ledgerid of length 9 and 10 because of order issue in HierarchicalLedgerRangeIterator
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-958'>BOOKKEEPER-958</a>] - ZeroBuffer readOnlyBuffer returns ByteBuffer with 0 remaining bytes for length > 64k
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-959'>BOOKKEEPER-959</a>] - ClientAuthProvider and BookieAuthProvider Public API used Protobuf Shaded classes
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-976'>BOOKKEEPER-976</a>] - Fix license headers with "Copyright 2016 The Apache Software Foundation"
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-980'>BOOKKEEPER-980</a>] - BookKeeper Tools doesn't process the argument correctly
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-981'>BOOKKEEPER-981</a>] - NullPointerException in RackawareEnsemblePlacementPolicy while running in Docker Container
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-984'>BOOKKEEPER-984</a>] - BookieClientTest.testWriteGaps tested
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-986'>BOOKKEEPER-986</a>] - Handle Memtable flush failure
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-987'>BOOKKEEPER-987</a>] - BookKeeper build is broken due to the shade plugin for commit ecbb053e6e
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-988'>BOOKKEEPER-988</a>] - Missing license headers
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-989'>BOOKKEEPER-989</a>] - Enable travis CI for bookkeeper git
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-999'>BOOKKEEPER-999</a>] - BookKeeper client can leak threads
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1013'>BOOKKEEPER-1013</a>] - Fix findbugs errors on latest master
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1018'>BOOKKEEPER-1018</a>] - Allow client to select older V2 protocol (no protobuf)
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1020'>BOOKKEEPER-1020</a>] - Fix Explicit LAC tests on master
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1021'>BOOKKEEPER-1021</a>] - Improve the merge script to handle github reviews api
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1031'>BOOKKEEPER-1031</a>] - ReplicationWorker.rereplicate fails to call close() on ReadOnlyLedgerHandle
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1044'>BOOKKEEPER-1044</a>] - Entrylogger is not readding rolled logs back to the logChannelsToFlush list when exception happens while trying to flush rolled logs
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1047'>BOOKKEEPER-1047</a>] - Add missing error code in ZK setData return path
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1058'>BOOKKEEPER-1058</a>] - Ignore already deleted ledger on replication audit
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1061'>BOOKKEEPER-1061</a>] - BookieWatcher should not do ZK blocking operations from ZK async callback thread
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1065'>BOOKKEEPER-1065</a>] - OrderedSafeExecutor should only have 1 thread per bucket
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1071'>BOOKKEEPER-1071</a>] - BookieRecoveryTest is failing due to a Netty4 IllegalReferenceCountException
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1072'>BOOKKEEPER-1072</a>] - CompactionTest is flaky when disks are almost full
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1073'>BOOKKEEPER-1073</a>] - Several stats provider related changes.
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1074'>BOOKKEEPER-1074</a>] - Remove JMX Bean
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1075'>BOOKKEEPER-1075</a>] - BK LedgerMetadata: more memory-efficient parsing of configs
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1076'>BOOKKEEPER-1076</a>] - BookieShell should be able to read the 'FENCE' entry in the log
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1077'>BOOKKEEPER-1077</a>] - BookKeeper: Local Bookie Journal and ledger paths
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1079'>BOOKKEEPER-1079</a>] - shell lastMark throws NPE
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1098'>BOOKKEEPER-1098</a>] - ZkUnderreplicationManager can build up an unbounded number of watchers
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1101'>BOOKKEEPER-1101</a>] - BookKeeper website menus not working under https
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1102'>BOOKKEEPER-1102</a>] - org.apache.bookkeeper.client.BookKeeperDiskSpaceWeightedLedgerPlacementTest.testDiskSpaceWeightedBookieSelectionWithBookiesBeingAdded is unreliable
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1103'>BOOKKEEPER-1103</a>] - LedgerMetadataCreateTest bug in ledger id generation causes intermittent hang
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1104'>BOOKKEEPER-1104</a>] - BookieInitializationTest.testWithDiskFullAndAbilityToCreateNewIndexFile testcase is unreliable
+</li>
+</ul>
+
+#### Improvement
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-612'>BOOKKEEPER-612</a>] - RegionAwarePlacement Policy
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-748'>BOOKKEEPER-748</a>] - Move fence requests out of read threads
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-757'>BOOKKEEPER-757</a>] - Ledger Recovery Improvement
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-759'>BOOKKEEPER-759</a>] - bookkeeper: delay ensemble change if it doesn't break ack quorum requirement
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-772'>BOOKKEEPER-772</a>] - Reorder read sequnce
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-874'>BOOKKEEPER-874</a>] - Explict LAC from Writer to Bookies
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-881'>BOOKKEEPER-881</a>] - upgrade surefire plugin to 2.19
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-887'>BOOKKEEPER-887</a>] - Allow to use multiple bookie journals
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-922'>BOOKKEEPER-922</a>] - Create a generic (K,V) map to store ledger metadata
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-935'>BOOKKEEPER-935</a>] - Publish sources and javadocs to Maven Central
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-937'>BOOKKEEPER-937</a>] - Upgrade protobuf to 2.6
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-944'>BOOKKEEPER-944</a>] - Multiple issues and improvements to BK Compaction.
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-945'>BOOKKEEPER-945</a>] - Add counters to track the activity of auditor and replication workers
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-946'>BOOKKEEPER-946</a>] - Provide an option to delay auto recovery of lost bookies
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-961'>BOOKKEEPER-961</a>] - Assing read/write request for same ledger to a single thread
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-962'>BOOKKEEPER-962</a>] - Add more journal timing stats
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-963'>BOOKKEEPER-963</a>] - Allow to use multiple journals in bookie
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-964'>BOOKKEEPER-964</a>] - Add concurrent maps and sets for primitive types
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-966'>BOOKKEEPER-966</a>] - change the bookieServer cmdline to make conf-file and option co-exist
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-968'>BOOKKEEPER-968</a>] - Entry log flushes happen on log rotation and cause long spikes in IO utilization
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-970'>BOOKKEEPER-970</a>] - Bump zookeeper version to 3.5
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-971'>BOOKKEEPER-971</a>] - update bk codahale stats provider version
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-998'>BOOKKEEPER-998</a>] - Increased the max entry size to 5MB
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1001'>BOOKKEEPER-1001</a>] - Make LocalBookiesRegistry.isLocalBookie() public
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1002'>BOOKKEEPER-1002</a>] - BookieRecoveryTest can run out of file descriptors
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1003'>BOOKKEEPER-1003</a>] - Fix TestDiskChecker so it can be used on /dev/shm
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1004'>BOOKKEEPER-1004</a>] - Allow bookie garbage collection to be triggered manually from tests
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1007'>BOOKKEEPER-1007</a>] - Explicit LAC: make the interval configurable in milliseconds instead of seconds
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1008'>BOOKKEEPER-1008</a>] - Move to netty4
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1010'>BOOKKEEPER-1010</a>] - Bump up Guava version to 20.0
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1022'>BOOKKEEPER-1022</a>] - Make BookKeeperAdmin implement AutoCloseable
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1039'>BOOKKEEPER-1039</a>] - bk-merge-pr.py ask to run findbugs and rat before merge
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1046'>BOOKKEEPER-1046</a>] - Avoid long to Long conversion in OrderedSafeExecutor task submit
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1048'>BOOKKEEPER-1048</a>] - Use ByteBuf in LedgerStorageInterface
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1050'>BOOKKEEPER-1050</a>] - Cache journalFormatVersionToWrite when starting Journal
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1051'>BOOKKEEPER-1051</a>] - Fast shutdown for GarbageCollectorThread
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1052'>BOOKKEEPER-1052</a>] - Print autorecovery enabled or not in bookie shell
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1053'>BOOKKEEPER-1053</a>] - Upgrade RAT maven version to 0.12 and ignore Eclipse project files
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1055'>BOOKKEEPER-1055</a>] - Optimize handling of masterKey in case it is empty
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1056'>BOOKKEEPER-1056</a>] - Removed PacketHeader serialization/deserialization allocation
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1063'>BOOKKEEPER-1063</a>] - Use executure.execute() instead of submit() to avoid creation of unused FutureTask
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1066'>BOOKKEEPER-1066</a>] - Introduce GrowableArrayBlockingQueue
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1068'>BOOKKEEPER-1068</a>] - Expose ByteBuf in LedgerEntry to avoid data copy
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1069'>BOOKKEEPER-1069</a>] - If client uses V2 proto, set the connection to always decode V2 messages
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1083'>BOOKKEEPER-1083</a>] - Improvements on OrderedSafeExecutor
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1084'>BOOKKEEPER-1084</a>] - Make variables finale if necessary
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1085'>BOOKKEEPER-1085</a>] - Introduce the AlertStatsLogger
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1090'>BOOKKEEPER-1090</a>] - Use LOG.isDebugEnabled() to avoid unexpected allocations
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1096'>BOOKKEEPER-1096</a>] - When ledger is deleted, along with leaf node all the eligible branch nodes also should be deleted in ZooKeeper.
+</li>
+</ul>
+
+#### New Feature
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-390'>BOOKKEEPER-390</a>] - Provide support for ZooKeeper authentication
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-391'>BOOKKEEPER-391</a>] - Support Kerberos authentication of bookkeeper
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-575'>BOOKKEEPER-575</a>] - Bookie SSL support
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-670'>BOOKKEEPER-670</a>] - Longpoll Read & Piggyback Support
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-912'>BOOKKEEPER-912</a>] - Allow EnsemblePlacementPolicy to choose bookies using ledger custom data (multitenancy support)
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-928'>BOOKKEEPER-928</a>] - Add custom client supplied metadata field to LedgerMetadata
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-930'>BOOKKEEPER-930</a>] - Option to disable Bookie networking
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-941'>BOOKKEEPER-941</a>] - Introduce Feature Switches For controlling client and server behavior
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-948'>BOOKKEEPER-948</a>] - Provide an option to add more ledger/index directories to a bookie
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-950'>BOOKKEEPER-950</a>] - Ledger placement policy to accomodate different storage capacity of bookies
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-969'>BOOKKEEPER-969</a>] - Security Support
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-983'>BOOKKEEPER-983</a>] - BookieShell Command for LedgerDelete
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-991'>BOOKKEEPER-991</a>] - bk shell - Get a list of all on disk files
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-992'>BOOKKEEPER-992</a>] - ReadLog Command Enhancement
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1019'>BOOKKEEPER-1019</a>] - Support for reading entries after LAC (causal consistency driven by out-of-band communications)
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1034'>BOOKKEEPER-1034</a>] - When all disks are full, start Bookie in RO mode if RO mode is enabled
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1067'>BOOKKEEPER-1067</a>] - Add Prometheus stats provider
+</li>
+</ul>
+
+#### Story
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-932'>BOOKKEEPER-932</a>] - Move to JDK 8
+</li>
+</ul>
+
+#### Task
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-931'>BOOKKEEPER-931</a>] - Update the committers list on website
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-996'>BOOKKEEPER-996</a>] - Apache Rat Check Failures
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1012'>BOOKKEEPER-1012</a>] - Shade and relocate Guava
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1027'>BOOKKEEPER-1027</a>] - Cleanup main README and main website page
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1038'>BOOKKEEPER-1038</a>] - Fix findbugs warnings and upgrade to 3.0.4
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1043'>BOOKKEEPER-1043</a>] - Upgrade Apache Parent Pom Reference to latest version
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1054'>BOOKKEEPER-1054</a>] - Add gitignore file
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1059'>BOOKKEEPER-1059</a>] - Upgrade to SLF4J-1.7.25
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1060'>BOOKKEEPER-1060</a>] - Add utility to use SafeRunnable from Java8 Lambda
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1070'>BOOKKEEPER-1070</a>] - bk-merge-pr.py use apache-rat:check goal instead of rat:rat
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1091'>BOOKKEEPER-1091</a>] - Remove Hedwig from BookKeeper website page
+</li>
+</ul>
+
+#### Test
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-967'>BOOKKEEPER-967</a>] - Create new testsuite for testing RackAwareEnsemblePlacementPolicy using ScriptBasedMapping.
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1045'>BOOKKEEPER-1045</a>] - Execute tests in different JVM processes
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1064'>BOOKKEEPER-1064</a>] - ConcurrentModificationException in AuditorLedgerCheckerTest
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1078'>BOOKKEEPER-1078</a>] - Local BookKeeper enhancements for testability
+</li>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-1097'>BOOKKEEPER-1097</a>] - GC test when no WritableDirs
+</li>
+</ul>
+
+#### Wish
+<ul>
+<li>[<a href='https://issues.apache.org/jira/browse/BOOKKEEPER-943'>BOOKKEEPER-943</a>] - Reduce log level of AbstractZkLedgerManager for register/unregister ReadOnlyLedgerHandle
+</li>
+</ul>
-[list to issues list]
+### Github
+- [https://github.com/apache/bookkeeper/milestone/1](https://github.com/apache/bookkeeper/milestone/1)
diff --git a/site/releases.md b/site/releases.md
index 7680f19..9ad9eb0 100644
--- a/site/releases.md
+++ b/site/releases.md
@@ -27,9 +27,15 @@ Client Guide | API docs
## News
-### [date] Release 4.5.0 available
+### 10 August, 2017: Release 4.5.0 available
-[INSERT SUMMARY]
+This is the fifth release of BookKeeper as an Apache Top Level Project!
+
+The 4.5.0 release incorporates hundreds of new fixes, improvements, and features since previous major release, 4.4.0,
+which was released over a year ago. It is a big milestone in Apache BookKeeper community, converging from three
+main branches (Salesforce, Twitter and Yahoo).
+
+See [BookKeeper 4.5.0 Release Notes](../docs/4.5.0/overview/releaseNotes) for details.
### 16 May, 2016: release 4.4.0 available
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