cleversafe跨vault读写实现的初步分析。

JSCSI是cleversafe中用的第三方的源代码，里面有很多类或包是没用的。

即使是cleversafe的源代码，有很多是其本身的一些试验性代码，在软件运行过程中是不起作用的。

 

另外，跨vault读写的工作和加入metadata的工作也不适合在scsi这一层来做，初步看应该在grid层以下。

 

 

 

 

首先，下面这个xml是很重要的，如果说cleversafe的代码不好读的话，这个文件是恶首之一。

 

dsnet-accesser/conf/core-org-bindings.xml

 

<?xml version="1.0"?> <bindns:bindings xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:eval="http://cleversafe.org/config/evaluator" xmlns:bindns="http://cleversafe.org/config/bindings"> <!-- Credentials --> <bindns:binding requiresInterface="org.cleversafe.authentication.CredentialsManager"> <bindns:implementation class="org.cleversafe.authentication.PropertiesFileCredentialsManager" default="true"/> </bindns:binding> <!-- Read Controller --> <bindns:binding requiresInterface="org.cleversafe.layer.grid.ReadControllerFactory"> <bindns:implementation class="org.cleversafe.layer.grid.smartcontroller.SmartReadControllerFactory" default="true" referral="smart"/> <bindns:implementation class="org.cleversafe.layer.grid.simplecontroller.SimpleReadControllerFactory" referral="simple"/> </bindns:binding> <!-- Write Controller --> <bindns:binding requiresInterface="org.cleversafe.layer.grid.WriteControllerFactory"> <bindns:implementation class="org.cleversafe.layer.grid.smartcontroller.SmartWriteControllerFactory" default="true" referral="smart"/> <bindns:implementation class="org.cleversafe.layer.grid.simplecontroller.SimpleWriteControllerFactory" referral="simple"> <bindns:param name="write-tolerance"> <eval:literal type="int" value="2"/> </bindns:param> </bindns:implementation> </bindns:binding> <!-- Serialization (ProtocolMessageFactory) --> <bindns:binding kind="Serialization" requiresInterface="org.cleversafe.serialization.ProtocolMessageFactory"> <bindns:implementation class="org.cleversafe.serialization.raw.RawGridProtocolMessageFactory" default="true" referral="raw"/> </bindns:binding> <!-- Connections --> <bindns:binding kind="Connection" requiresInterface="org.cleversafe.layer.communication.Connector"> <bindns:implementation class="org.cleversafe.layer.communication.network.mina.MinaConnector" referral="mina" default="true"/> <!-- <bindns:implementation class="org.cleversafe.storage.ss.SliceServerMemoryConnector" referral="memory"/> --> </bindns:binding> <bindns:binding kind="ConnectionManager" requiresInterface="org.cleversafe.layer.communication.ConnectorManager"> <bindns:implementation class="org.cleversafe.layer.communication.policy.SmartConnectorManager" default="true"/> </bindns:binding> <bindns:binding kind="Acceptor" requiresInterface="org.cleversafe.layer.communication.Acceptor"> <bindns:implementation class="org.cleversafe.layer.communication.network.mina.MinaAcceptor" default="true" referral="network"/> </bindns:binding> <!-- IDAs --> <bindns:binding kind="IDA" requiresInterface="org.cleversafe.ida.InformationDispersalCodec"> <bindns:implementation class="org.cleversafe.ida.CosetCode.CosetInformationDispersalCodec" referral="cosetcodec" minVersion="1.0" maxVersion="1.0"/> <bindns:implementation class="org.cleversafe.ida.optimizedcauchy.CauchyInformationDispersalCodec" referral="cauchy" minVersion="1.0" maxVersion="1.0"/> <!-- Deprecated referral "optimizedcauchy". To be removed soon --> <bindns:implementation class="org.cleversafe.ida.optimizedcauchy.CauchyInformationDispersalCodec" referral="optimizedcauchy" minVersion="1.0" maxVersion="1.0"/> <bindns:implementation class="org.cleversafe.ida.replicate.ReplicateInformationDispersalCodec" referral="replicate" minVersion="1.0" maxVersion="1.0"/> </bindns:binding> <!-- Codecs --> <bindns:binding kind="Codec" requiresInterface="org.cleversafe.codec.Codec"> <bindns:implementation class="org.cleversafe.codec.misc.NullCodec" referral="null" minVersion="1.0" maxVersion="1.0"/> <bindns:implementation class="org.cleversafe.codec.misc.TranspositionCodec" referral="transposition" minVersion="1.0" maxVersion="1.0"/> <bindns:binding kind="Encryption"/> <bindns:binding kind="Integrity"> <!-- referral "crc" is deprecated in favor of "crc-32" --> <bindns:implementation class="org.cleversafe.codec.integrity.CRCIntegrityCodec" referral="crc" minVersion="1.0" maxVersion="1.0"/> <bindns:implementation class="org.cleversafe.codec.integrity.CRCIntegrityCodec" referral="crc-32" minVersion="1.0" maxVersion="1.0"/> </bindns:binding> <bindns:binding kind="Compression"/> </bindns:binding> <!-- Slice Stores --> <bindns:binding kind="SliceStore" requiresInterface="org.cleversafe.layer.slicestore.SliceStore"> <bindns:implementation class="org.cleversafe.layer.slicestore.block.BlockFileSliceStore" referral="block-file"/> <bindns:implementation class="org.cleversafe.layer.slicestore.block.BlockMultiFileSliceStore" referral="block-multi-file"/> <bindns:implementation class="org.cleversafe.layer.slicestore.remote.RemoteSliceStore" referral="remote"/> <bindns:implementation class="org.cleversafe.layer.slicestore.unreliable.UnreliableSliceStore" referral="unreliable"/> </bindns:binding> <bindns:binding kind="MultiFileStorage"> <bindns:implementation class="org.cleversafe.layer.slicestore.block.BlockMultiFileSliceStore$FileStorageDefinition" default="true"/> </bindns:binding> <!-- Slice Store Managers --> <bindns:binding kind="SliceStoreManager" requiresInterface="org.cleversafe.layer.slicestore.SliceStoreManager"> <bindns:implementation class="org.cleversafe.layer.slicestore.block.BlockFileSliceStoreManager" referral="block-file"/> <bindns:implementation class="org.cleversafe.layer.slicestore.block.BlockMultiFileSliceStoreManager" referral="block-multi-file"/> </bindns:binding> <bindns:binding kind="MultiFilePartition"> <bindns:implementation class="org.cleversafe.layer.slicestore.block.BlockMultiFileSliceStoreManager$PartitionDefinition" default="true"/> </bindns:binding> <bindns:binding kind="SliceStoreDescriptorManager"> <bindns:implementation class="org.cleversafe.layer.slicestore.SliceStoreDescriptorManager" default="true"/> </bindns:binding> <bindns:binding kind="SliceStoreWrapper" requiresInterface="org.cleversafe.layer.slicestore.SliceStoreWrapper"> <bindns:implementation class="org.cleversafe.layer.slicestore.unreliable.UnreliableWrapper" referral="unreliable"/> </bindns:binding> <!-- Slice Store Info --> <bindns:binding kind="SliceStoreInfo"> <bindns:implementation class="org.cleversafe.layer.slicestore.block.BlockFileSliceStoreInfo" referral="block-file"/> </bindns:binding> <!-- Vaults --> <bindns:binding kind="Vault" requiresInterface="org.cleversafe.vault.Vault"/> <bindns:binding kind="VaultManager" requiresInterface="org.cleversafe.vault.VaultManager"> <bindns:implementation class="org.cleversafe.vault.managers.LocalFileVaultManager" referral="file"/> </bindns:binding> <bindns:binding kind="VaultACL" requiresInterface="org.cleversafe.vault.VaultACL"> <bindns:implementation class="org.cleversafe.vault.FileVaultACL" referral="file" default="true"/> </bindns:binding> <bindns:binding requiresInterface="org.cleversafe.vault.VaultResolver"> <bindns:implementation class="org.cleversafe.vault.VaultFileResolver" default="true"/> </bindns:binding> <bindns:binding requiresInterface="org.cleversafe.vault.VaultLoader"> <bindns:implementation class="org.cleversafe.vault.XMLVaultLoader" default="true"/> </bindns:binding> <bindns:binding kind="AuthenticationFacilitator" requiresInterface="org.cleversafe.authentication.AuthenticationFacilitator"> <bindns:implementation class="org.cleversafe.authentication.JAASPasswordAuthenticationFacilitator" default="true"/> </bindns:binding> <bindns:binding kind="AuthenticationFacilitatorConfiguration" requiresInterface="org.cleversafe.authentication.AuthenticationFacilitatorConfiguration"> <bindns:implementation class="org.cleversafe.authentication.JAASConfiguration" default="true"/> </bindns:binding> </bindns:bindings>

 

 

 

 

对远程多个slice服务器读写的实现是在

中

org.cleversafe.layer.slicestore.remote.RemoteSliceStore.readImpl(List<SliceName>)

实现的。

 

但是调用的话是在主要是在org.cleversafe.layer.grid.smartcontroller.ReadStateMachine中

 

其中的SliceNames，

是存在org.cleversafe.vault.BaseVault.sliceStores中的。

 

好了，有了这些，基本上就全部都能改了。

 

注 ：SliceName的内容是什么，还不太清楚，可以整体编译后，运行log出来看看。以上仅是读代码后的猜测，具体还要log出来才知道是否正确。

 

 

 

另外，中间数据和mapping树之类的东西可以用java.io.RandomAccessFile来写到文件中。

 

 

 

 

 

 

 

 

 

 

 

 

#############################我是结束线#####################################

 

 

#############################我是结束线#####################################

 

 

#############################我是结束线#####################################

 

 

 

 

下面是跟着某人的思路看的，看就看了，也不删了.................

 

 

原始的jSCSI##################################################################

首先，在jSCSI大包里，读写最终是用：

org.jscsi.connection.Session.read(Object, ByteBuffer, int, long)

来实现的。

当jscsi相关模块收到的socket来的读写命令，交给session来处理的，

session本身是一个线程，通过：head = taskQueue.poll();来监视排列。

          head.execute();
          final Object thread = head.getCaller();

这里会判断是读或写，分别调用相应的模块 。

 

 

 

 

在这里 head的接口调用是关键：

 

对于读写来说head是一个 IOTask类，读写分别对应于ReadTask，WriteTask。

 

然后是一堆的继承和调用关系，最后现出原型：

org.jscsi.JSCSIDevice.read(long, byte[])

第一个是地址，二个是对应的内存块。读就是把地址中的数据读到后的内存块。

原始的jSCSI##################################################################完

如果还是原始的jSCSI的话：

再从头找回来，读的实现是在：

org.jscsi.connection.Session.ReadTask.execute()中的

  phase.read(session, buffer, logicalBlockAddress, length);

又是一堆的继承和调用关系，

最后应该在：

org.jscsi.connection.FullFeaturePhase.read(Session, ByteBuffer, int, long)

 

 

 

但是在cleversafe的实现

 

ISCSITargetService 中的
         LogicalUnit lu = new GridLogicalUnit(controller);

调用的是GridLogicalUnit(controller);

 

 

 

回过头来看一下：