MDSTableClient类相关分析

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MDSTableClient类用于和MDSTableServer通信，向MDSTableServer类发送消息以及从MDSTableServer类接收消息回复

MDSTableClient::handle_request()          client端总路由调度函数，根据消息的操作类型不同，调用不同的handle_*()函数进行处理

|__TABLESERVER_OP_QUERY_REPLY

     |__handle_query_result()

|__TABLESERVER_OP_AGREE

     |__对于回复在pending_prepare数组中

          |__设置pending_prepare[reqid].ptid = tid

          |__设置pending_prepare[reqid].pbl = m->bl

          |__删除pending_prepare[reqid]

          |__设置prepared_update[tid] = reqid

     |__对于回复在prepared_update数组中

          |__重复回复

     |__对于回复在pending_commit数组中

     |__对于回复不再上述数组中

          |__创建MMDSTableRequest类消息(TABLESERVER_OP_ROLLBACK)

          |__mds->send_message_mds()               将消息发送给Server

|__TABLESERVER_OP_ACK

     |__对于回复在pending_commit数组中

          |__删除pending_commit[tid]->pending_commit_tids[table]

          |__删除pending_commit[tid]

          |__mds->mdlog->start_submit_entry()

|__TABLESERVER_OP_SERVER_READY

     |__设置server_ready = true

     |__resend_queries()

     |__resend_prepares()

     |__resend_commits()

 

MDSTableClient::_logged_ack()          对于TABLESERVER_OP_ACK操作写log的回调函数

|__对于ack_waiters[tid]

     |__mds->queue_waiters(ack_waiters[tid])

     |__清除ack_waiters[tid]

 

MDSTableClient::_prepare()

|__对于tableserver未准备好，则将prepare消息插入到waiting_for_reqid数组中

|__获取reqid = ++last_reqid

|__填充pending_prepare[reqid]数组

|__若tableserver准备好

     |__创建MMDSTableRequest类消息(TABLESERVER_OP_PREPARE)

     |__mds->send_message_mds()          发送消息到tableserver

 

MDSTableClient::commit()

|__删除prepared_update[tid]

|__设置pending_commit[tid] = ls

|__若tableserver准备好

     |__创建MMDSTableRequest类消息(TABLESERVER_OP_COMMIT)

     |__mds->send_message_mds()          发送消息到tableserver

 

MDSTableClient::got_journaled_agree()

|__pending_commit[tid] = ls

 

MDSTableClient::got_journaled_ack()

|__删除pending_commit[tid]

 

MDSTableClient::resend_prepares()

|__遍历waiting_for_reqid数组

     |__将该数组中的内容复制到pending_prepare[++last_reqid]

     |__删除waiting_for_reqid数组对应的项

|__遍历pending_prepare数组

     |__创建MMDSTableRequest类消息(TABLESERVER_OP_PREPARE)

     |__mds->send_message_mds()          将类消息发送给tableserver

 

MDSTableClient::resend_commits()

|__遍历pending_commit数组

     |__创建MMDSTableRequest类消息(TABLESERVER_OP_COMMIT)

     |__mds->send_message_mds()          将类消息发送给tableserver

 

MDSTableClient::handle_mds_failure()

|__设置server_ready = false

 

SnapClient类继承于MDSTableClient类，实际上SnapClient就是封装了一些处理函数，SnapClient具体操作函数说明如下：

SnapClient::prepare_create()

|__设置op = TABLE_OP_CREATE

|__将op/dirino/name/stamp序列化到bufferlist中

|__MDSTableClient::_prepare()

 

SnapClient::prepare_create_realm()

|__设置op = TABLE_OP_CREATE

|__将op/ino序列化到bufferlist中

|__MDSTableClient::_prepare()

 

SnapClient::prepare_destroy()

|__设置op = TABLE_OP_DESTROY

|__将op/ino/snapid序列化到bufferlist中

|__MDSTableClient::_prepare()

 

SnapClient::prepare_update()

|__设置op = TABLE_OP_UPDATE

|__将op/ino/snapid/name/stamp序列化到bufferlist中

|__MDSTableClient::_prepare()

 

SnapClient和MDSTableClient的对应关系如下图所示：

转载于:https://my.oschina.net/linuxhunter/blog/706801