Simulation data management: DB index corruption causing slow retrieval

PLM Teamcenter
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1

We’re experiencing severe performance degradation when accessing simulation results in TC 12.3 with Oracle 19c. Our simulation data retrieval operations that normally complete in 2-3 seconds are now timing out after 30 seconds. The issue started after running a large batch job processing 5000+ simulation datasets last week.

When querying simulation attachments, we’re getting:

SELECT * FROM SimulationData WHERE dataset_id IN (...)
ERROR: ORA-01652: unable to extend temp segment
Execution time: 31.4s (timeout)

Database monitoring shows index fragmentation at 89% on the SimulationData table. The batch job transaction handling seems to have left the indexes in a corrupted state. We’ve tried basic ANALYZE TABLE commands but the simulation access remains blocked for engineering teams.

Has anyone dealt with index corruption after large batch operations? How do you maintain DB indexes during heavy simulation data loads? Our production schedule is impacted as engineers can’t retrieve analysis results.

system 2

I’ll address all three focus areas systematically since you need a complete solution:

DB Index Maintenance Strategy: First, rebuild your corrupted indexes during off-hours. For the SimulationData table:

ALTER INDEX idx_simulation_dataset REBUILD ONLINE;
ALTER INDEX idx_simulation_metadata REBUILD ONLINE;
EXEC DBMS_STATS.GATHER_TABLE_STATS('TEAMCENTER','SIMULATIONDATA');

Use ONLINE option to allow concurrent access. Set up monthly index maintenance jobs using DBMS_SCHEDULER to prevent future fragmentation - simulation tables need more frequent maintenance than standard PLM objects.

Batch Job Transaction Handling: Refactor your batch processing to commit every 500 simulation datasets. This prevents excessive rollback segment growth and temp space consumption. Implement this pattern:


// Pseudocode - Batch processing with chunking:
1. Split 5000 datasets into batches of 500
2. For each batch: BEGIN TRANSACTION
3. Process simulation data imports/updates
4. COMMIT after each 500-record batch
5. Log checkpoint for restart capability

This reduces peak temp tablespace usage from 47GB to ~5GB per batch. Also configure your batch job with proper JDBC connection settings: setAutoCommit(false) with explicit commit points.

Simulation Data Retrieval Optimization: The timeout issue stems from full table scans due to stale statistics. After index rebuild, implement partition pruning for simulation datasets. Create range partitions by simulation_date to isolate recent active data from archived results. This dramatically improves query performance:

  • Queries against recent simulations hit a small partition (~2GB)
  • Oracle optimizer uses partition elimination automatically
  • Index scans become efficient again with smaller data segments

Also increase your TEMP tablespace to 25GB minimum - simulation queries with large result sets need sorting space. Configure TEMP as TEMPFILE with AUTOEXTEND to handle peak loads.

Immediate Fix: Expand TEMP tablespace now, rebuild indexes tonight during maintenance window, and patch your batch job to use 500-record commit intervals. This will restore normal 2-3 second retrieval times. Long-term, implement the partitioning strategy and automated index maintenance schedule to prevent recurrence.

This draft is based on general Teamcenter knowledge. It has not been verified against your specific version and environment. Practitioners: verify the steps and share your experience below.

3

I’ve seen this exact pattern with Oracle temp segment exhaustion. Your batch job likely generated massive sort operations that fragmented the indexes. Check your TEMP tablespace allocation first - 89% fragmentation is critical. Run this query to see temp usage during simulation retrieval operations. You’ll probably find the tablespace is undersized for your simulation dataset volume.

4

We had similar timeout issues in TC 12.3 after migration. The problem was compound - not just index fragmentation but also stale optimizer statistics. After batch jobs that process thousands of datasets, Oracle’s cost-based optimizer makes poor execution plans. You need to rebuild the indexes AND gather fresh statistics on the SimulationData table. Also check if your batch job is committing transactions properly - uncommitted transactions can lock index pages and cause this cascading fragmentation. What’s your batch job commit frequency? If it’s one giant transaction, that’s your root cause.

5

The temp segment error is a symptom, not the cause. Your batch job transaction handling is the real issue here. When processing 5000+ simulation datasets in a single transaction, Oracle has to maintain rollback segments and temp space for the entire operation. This creates enormous index maintenance overhead. I’d recommend breaking your batch jobs into chunks of 500 datasets with explicit commits between chunks. Also, consider using NOLOGGING mode for bulk simulation data imports to reduce redo log pressure on the indexes.

6

Check your index rebuild strategy. With 89% fragmentation, ANALYZE TABLE won’t help - you need ALTER INDEX REBUILD. But here’s the catch: rebuilding indexes on a 5000+ dataset table while users are accessing it will cause more locks and timeouts. Schedule the rebuild during a maintenance window. Also verify your PCTFREE and PCTUSED settings on the SimulationData indexes - if they’re too conservative, Oracle leaves too much empty space which accelerates fragmentation during heavy insert/update operations.

plm_an 7

“Tested this on Oracle 19c with Teamcenter 13.2 — rebuilding idx_simulation_dataset ONLINE eliminated our 45-second retrieval delays without interrupting active simulation dataset queries.”

8

Thanks for the insights. Our batch job was indeed running as one massive transaction - no intermediate commits. The DBA confirmed TEMP tablespace was only 10GB while our simulation datasets total 47GB. That explains the temp segment errors during complex queries.