INC-126129 · Issue 569666
PropertyToColumnMap made more robust
Resolved in Pega Version 8.1.9
The DF_ProcessEmails dataflow was intermittently failing with a StageException error. This was traced to schema changes being propagated asynchronously by system pulse, which seem to have caused PropertyToColumnMap to cache stale schema. To resolve this, if the property mapping is not found the first time, the system will make a second attempt to get the mapping. Additional logging has also been added for better diagnostics.
INC-128385 · Issue 564521
Behavior made consistent between SSA and legacy engines
Resolved in Pega Version 8.1.9
There was a behavioral disparity between the legacy execution engine and the SSA engine where the latter was not creating a new page when the index was one above the size of the page list. This has now been corrected in order to make the SSA behavior fully backward compatible with the legacy engine, i.e. a new blank page will be added to the list if the index is one above the size of the list.
INC-129222 · Issue 568530
Handling improvements for commit logs
Resolved in Pega Version 8.1.9
The ADM commit log logs the number of unconsumed messages that are going to expire. In certain circumstances, it can include unconsumed messages that are not going to expire in the count. Because they are not expired and removed, the environment was running out of disk space due to the ADM commitlogs table growing larger than expected and performance issues were seen. To resolve this, a new adm_commitlog.adm_responses_commit_log_date_tiered table has been created, with a default_time_to_live of 24 hours. DateTieredCompactionStrategy has been set with max_window_size_seconds as 24hrs and tombstone_compaction_interval as 24hrs.
INC-132976 · Issue 580685
Performance improvements for Test Strategy data flow
Resolved in Pega Version 8.1.9
In the Test Strategy panel under Single case -> "Settings", selecting the "Data flow" option and choosing CustomerData dataflow was taking an excessive amount of time to run on a system with an extremely large database. To improve performance, two areas have been addressed: 1) the default behavior for record key suggestions in the test panel has been modified to collect only the ID as the additional data is not necessary at that time; 2) a DSS has been added that will opt out of reading and collecting the customer IDs in order to minimize data stored on the clipboard.
INC-138037 · Issue 586593
Strategy handling updated for very large systems using IH summary
Resolved in Pega Version 8.1.9
When a Strategy in a Real-time dataflow used IH Summary on a system with more than 5000 groups for one eventKey, the message "Error retrieving aggregates from Cassandra KVS" intermittently appeared. Investigation showed that if the number of result rows was greater than the FETCH_SIZE (set to 5000), it meant another read to Cassandra was required and an exception was generated. To resolve this, updates have been made so that instead of returning maps, the system will return iterators and change them to map on the calling thread.
SR-D92734 · Issue 553412
Simulation can take Data flow type as destination
Resolved in Pega Version 8.1.9
Support has been added for Data flow functionality as simulation target and data transform in simulation input.
INC-203994 · Issue 698853
DSS added to handle merges with lower versions of Postgres
Resolved in Pega Version 8.7.1
After update, executing the batch campaign with volume constraint resulted in the second data flow DF_Wait failing with error message "ERROR: number of columns (1844) exceeds limit (1664)". This was due to the database set’s change (in 8.5) to use the database layer’s merge statement. Prior to that, the logic used "deletes and inserts". Depending on the version of Postsgres, the generated SQL statement for a merge statement is different. The “INSERT … ON CONFLICT … UPDATE” syntax is generated for Postgres 9.5+ AND when there is a PK constraint defined for the DB table. Otherwise, the complex UPSERT statement (old syntax) is generated, as was the case in this issue. This is a known issue in the Postgres server software where it mis-interprets the number of columns involved. i.e., it mistakenly counts the number of columns twice. As a result, the actual maximum columns allowed is only half of the official limit (1664). The same UPSERT statement does not cause the “exceeds limit” exception if there are 832 or fewer columns in the statement. To resolve this, an option has been provided to select between the “original logic” (deletes and inserts) and the “merge statements” logic by way of the DSS “decision/datasets/db/useMergeStatementForUpdates”. Setting “true” will use the merge statement logic, and setting “false” will use deletes and inserts. When the DSS is not defined, the default is "true" and the system will use merge statements in the form preferred by Postgres 9.5+.
INC-180246 · Issue 699700
Support for apostrophe added to keyword tokenization
Resolved in Pega Version 8.7.1
A keyword containing an apostrophe was not detected properly in Text extraction model. This has been resolved by updating the annotator used in the tokenization.
INC-193399 · Issue 688115
DSS added to handle merges with lower versions of Postgres
Resolved in Pega Version 8.7.1
After update, executing the batch campaign with volume constraint resulted in the second data flow DF_Wait failing with error message "ERROR: number of columns (1844) exceeds limit (1664)". This was due to the database set’s change (in 8.5) to use the database layer’s merge statement. Prior to that, the logic used "deletes and inserts". Depending on the version of Postsgres, the generated SQL statement for a merge statement is different. The “INSERT … ON CONFLICT … UPDATE” syntax is generated for Postgres 9.5+ AND when there is a PK constraint defined for the DB table. Otherwise, the complex UPSERT statement (old syntax) is generated, as was the case in this issue. This is a known issue in the Postgres server software where it mis-interprets the number of columns involved. i.e., it mistakenly counts the number of columns twice. As a result, the actual maximum columns allowed is only half of the official limit (1664). The same UPSERT statement does not cause the “exceeds limit” exception if there are 832 or fewer columns in the statement. To resolve this, an option has been provided to select between the “original logic” (deletes and inserts) and the “merge statements” logic by way of the DSS “decision/datasets/db/useMergeStatementForUpdates”. Setting “true” will use the merge statement logic, and setting “false” will use deletes and inserts. When the DSS is not defined, the default is "true" and the system will use merge statements in the form preferred by Postgres 9.5+.
INC-193632 · Issue 679172
Cassandra driver metrics exposed for performance troubleshooting
Resolved in Pega Version 8.7.1
By default Cassandra driver metrics are now enabled. Metrics can be disabled by setting the dnode/disable_driver_metrics prconfig parameter.