8/13/2019 Guidelines for Deciding Between File

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 Guidelines for deciding between file or databasecheckpointing:++++++++++++++++1.Duplicate detection can only be done across multipleengines on different machines if a database is used tostore process engine data. If you are running faulttolerant process engines (that is, only one process engineis running at a particular time), or if all process enginesrun on the same machine, you can use a file system forprocess engine storage.2.For true fault tolerance, you must store the data in adatabase. You specify a JDBC Connection resource for thedatabase to be used when you configure your project inTIBCO Designer. The database is then one of the availableoptions on the Checkpoint Data Repository pop-upmenu.3.Because fault-tolerant engines are expected to be onseparate machines, you should specify to use a database forstorage for each process engine. This allows youto specifythe same JDBC Connection resource for the master andsecondary engines, and therefore all engines can share theinformation stored for process instancecheckpoints.4.Also, your servers may not have all of the necessarysoftware for restarting allof instances. For example, yourdatabase may reside on the same machine as your masterprocess engine. If that server goes down, any JDBCactivities will not be able to execute. Therefore, you maynot wish to load process definitions that use J

DBCactivities in your secondary process engine.++++++++++++++++++++++++++++++# Here you understand better which explain about advantagesand disadvantages ofdatabases storage and file storage.Most of the information a process engine stores areinformation about each service state when a checkpoint is taken.There is, however, some other internal informationstored by the engine. You canspecify that this informationis stored in the file system (the default) or in adatabasebased on your need.For some systems, using a file system for storage may besufficient. However, some functionality is only availablewhen you use a database for storing information aboutservice state:1.With a database for storage, fault-tolerant engines canrecover services up to acheckpoint. Without a database,running services cannot be recovered to their las

tcheckpoint.(File based is not recommended for FT. Also, otherwise thefile should be on the local machine else the performancewill be poor because it is quite obvious that file based istaking much longer than DB based checkpointing)2.With a database for storage, Wait/Notify activities canbe used to pass data between services running on differentmachines. Without a database, the wait and notifyactivities cannot communicate across machines.3.Duplicate detection can only be done across multipleengines on different machines if a database is used tostore process engine data. If you are running faulttolerant process engines (that is, only one process engineis running at a particular time), or if all process enginesrun on the same machine, you can use a file system forprocess engine storage.For better reliability using database over file s

ystem forcheckpoint storage is good option. taken. There is, however, some other internal informationstored by the engine.You can specify that this informationis stored in the file system (the default)or in a databasebased on your need.For some systems, using a file system for storage may besufficient. However, some functionality is only availablewhen you use a database for storing information aboutservice state:1.With a database for storage, fault-tolerant engines canrecover services up to acheckpoint. Without a database,running services cannot be recovered to their lastcheckpoint.(File based is not recommended for FT. Also, otherwise thefile shoul

8/13/2019 Guidelines for Deciding Between File

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d be on the local machine else the performancewill be poor because it is quite obvious that file based istaking much longer than DB based checkpointing)2.With a database for storage, Wait/Notify activities canbe used to pass data between services running on differentmachines. Without a database, the wait and notifyactivities cannot communicate across machines.3.Duplicate detection can only be done across multipleengines on different machines if a database is used tostore process engine data. If you are running faulttolerant process engines (that is, only one process engineis running at a particular time), or if all process enginesrun on the same machine, you can use a file system forprocess engine storage.For better reliability using database over file system forcheckpoint storage is good option.