pecl:mysqlnd_ms

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pecl:mysqlnd_ms [2012/04/17 11:01] – [Development steps (release planning)] uwpecl:mysqlnd_ms [2012/04/17 11:48] – [Raw Bin ideas (RFCs)] uw
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   * [open] Refine QoS session consistency server selection policy   * [open] Refine QoS session consistency server selection policy
     * [open] Support "wait for GTID". Currently we loop over all servers until we find a matching one. MySQL 5.6 allows SQL users either to fetch the latest GTID or SQL users can ask for a GTID and their request will block until the GTID has been replicated on the server. We should support the latter logic as well.     * [open] Support "wait for GTID". Currently we loop over all servers until we find a matching one. MySQL 5.6 allows SQL users either to fetch the latest GTID or SQL users can ask for a GTID and their request will block until the GTID has been replicated on the server. We should support the latter logic as well.
-    * [open] Remember the most current server and test this one first when searching for a GTID (a synchronous server). +    * [open] Remember the most current server and test this one first when searching for a GTID (a synchronous server). Use of cached information is possible for the duration of a read-only request sequence. The cache must be flushed and refreshed for every write.
  
   * [open] Improve load balancing   * [open] Improve load balancing
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 == Problem to solve / Idea == == Problem to solve / Idea ==
  
-MySQL replication is asnychronous. Slaves are //eventual consistent// because there is a time lag between an update on the master and the ability of all clients to read that update from the slaves. Slaves may serve stale data.+MySQL replication is asynchronous. Slaves are //eventual consistent// because there is a time lag between an update on the master and the ability of all clients to read that update from the slaves. Slaves may serve stale data.
  
 MySQL replication used for read scale-out requires applications to be able to cope with stale data. If stale data is acceptable, a replication system may replace a MySQL slave read access with an access to a local, eventually stale, cache. **The cache access will lower network latency resulting in faster reply to the query. Furthermore, it will reduce the load on the MySQL replication slaves, thus requiring less machines for a given read workload.** MySQL replication used for read scale-out requires applications to be able to cope with stale data. If stale data is acceptable, a replication system may replace a MySQL slave read access with an access to a local, eventually stale, cache. **The cache access will lower network latency resulting in faster reply to the query. Furthermore, it will reduce the load on the MySQL replication slaves, thus requiring less machines for a given read workload.**
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 +=== Refine QoS session consistency server selection policy ===
  
 +== Problem to solve / Idea ==
 +
 +Users can request session consistency. Session consistency guarantees that a user will only be redirected to nodes that have already replicated his changes. Currently we check the status of all configured nodes before we pick a node for statement execution. Checking the status causes extra load on the nodes. The load shall be optionally reduced with tweaking settings.
 +
 +== Feature description ==
pecl/mysqlnd_ms.txt · Last modified: 2017/09/22 13:28 by 127.0.0.1

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