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@ -873,7 +873,7 @@ primary_conninfo = 'host=192.168.1.50 port=5432 user=foo password=foopass' |
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might indicate that the master server is under heavy load, while |
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differences between <literal>sent_location</> and |
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<function>pg_last_xlog_receive_location</> on the standby might indicate |
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network delay, or that the the standby is under heavy load. |
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network delay, or that the standby is under heavy load. |
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</para> |
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</sect3> |
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@ -952,7 +952,7 @@ synchronous_replication = on |
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If the standby is the first matching standby, as specified in |
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<varname>synchronous_standby_names</> on the primary, the reply |
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messages from that standby will be used to wake users waiting for |
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confirmation the commit record has been received. These parameters |
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confirmation that the commit record has been received. These parameters |
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allow the administrator to specify which standby servers should be |
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synchronous standbys. Note that the configuration of synchronous |
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replication is mainly on the master. |
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@ -1002,10 +1002,10 @@ synchronous_replication = on |
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<para> |
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With synchronous replication options specified at the application level |
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(on the primary) we can offer sync rep for the most important changes, |
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without slowing down the bulk of the total workload. Application level |
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options are an important and practical tool for allowing the benefits of |
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synchronous replication for high performance applications. |
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(on the primary) we can offer synchronous replication for the most |
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important changes, without slowing down the bulk of the total workload. |
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Application level options are an important and practical tool for allowing |
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the benefits of synchronous replication for high performance applications. |
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</para> |
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<para> |
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@ -1029,7 +1029,7 @@ synchronous_replication = on |
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your last remaining sync standby. This can be achieved by naming multiple |
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potential synchronous standbys using <varname>synchronous_standby_names</>. |
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The first named standby will be used as the synchronous standby. Standbys |
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listed after this will takeover the role of synchronous standby if the |
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listed after this will take over the role of synchronous standby if the |
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first one should fail. |
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</para> |
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@ -1039,7 +1039,7 @@ synchronous_replication = on |
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the lag between standby and primary reaches zero for the first time |
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we move to real-time <literal>STREAMING</> state. |
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The catch-up duration may be long immediately after the standby has |
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been created. If the standby is shutdown, then the catch-up period |
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been created. If the standby is shut down, then the catch-up period |
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will increase according to the length of time the standby has been down. |
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The standby is only able to become a synchronous standby |
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once it has reached <literal>STREAMING</> state. |
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@ -1060,12 +1060,13 @@ synchronous_replication = on |
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<para> |
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If you really do lose your last standby server then you should disable |
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<varname>synchronous_standby_names</> and restart the primary server. |
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<varname>synchronous_standby_names</> and reload the configuration file |
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on the primary server. |
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</para> |
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<para> |
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If the primary is isolated from remaining standby severs you should |
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failover to the best candidate of those other remaining standby servers. |
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If the primary is isolated from remaining standby servers you should |
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fail over to the best candidate of those other remaining standby servers. |
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</para> |
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<para> |
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@ -1130,7 +1131,7 @@ synchronous_replication = on |
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and might stay down. To return to normal operation, a standby server |
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must be recreated, |
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either on the former primary system when it comes up, or on a third, |
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possibly new, system. Once complete the primary and standby can be |
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possibly new, system. Once complete, the primary and standby can be |
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considered to have switched roles. Some people choose to use a third |
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server to provide backup for the new primary until the new standby |
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server is recreated, |
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@ -1155,8 +1156,7 @@ synchronous_replication = on |
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<command>pg_ctl promote</> to fail over, <varname>trigger_file</> is |
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not required. If you're setting up the reporting servers that are |
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only used to offload read-only queries from the primary, not for high |
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availability purposes, you don't need to exit recovery in the standby |
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and promote it to a master. |
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availability purposes, you don't need to promote it. |
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</para> |
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</sect1> |
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