ttBulkCp Performance Degrade After Upgrade From 11.2.2.4.11 To 11.2.2.8.0

(Doc ID 2058115.1)

Last updated on SEPTEMBER 22, 2016

Applies to:

Oracle TimesTen In-Memory Database - Version 11.2.2.8.0 and later
Information in this document applies to any platform.

Symptoms

After upgrading from 11.2.2.4.11 to 11.2.2.8.0, ttBulkCp was very slow while loading data.

 

11.2.2.8.2
===========

< CacheAwtParallelism, 4 >
< ReplicationParallelism, 2 >

Load 1m rows into a simple 7 col customer table:

Command> host time ttBulkCp -i demodb4 cacheadm.customers customers_data.dmp;

customers_data.dmp:
    1000000 rows inserted
    1000000 rows total

real    1m5.052s
user    1m4.607s
sys     0m0.191s

The rows are propagated to Oracle as soon as the load starts. They're still being loaded on Oracle after load on TT finishes. This load on TT is over a minute.

11.2.2.4.11
===========

< CacheAwtParallelism, 4 >
< ReplicationParallelism, 2 >

host time ttBulkCp -i demodb4_11 cacheadm.customers customers_data.dmp

customers_data.dmp:
    1000000 rows inserted
    1000000 rows total

real    0m7.055s
user    0m6.730s
sys     0m0.299s

This completes on TT much quicker. Rows are not propagated to Oracle until after the load on TT finishes.

11.2.2.8.2
==========

< CacheAwtParallelism, 1 >
< ReplicationParallelism, 1 >

Command> host time ttBulkCp -i demodb1 cacheadm.customers customers_data.dmp

customers_data.dmp:
    1000000 rows inserted
    1000000 rows total

real    0m6.180s
user    0m5.837s
sys     0m0.261s

Here the time is comparable to 11.2.2.4.11 with CacheAwtParallelism=4; again
the load is done first on TT before propagation starts.

And another symptom is while loading data that CPU usage by both ttBulkCP and timestenrepd approaches 100%.

 

Changes

 Upgraded Database from 11.2.2.4.11 to 11.2.2.8.2

Cause

Sign In with your My Oracle Support account

Don't have a My Oracle Support account? Click to get started

My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms