Bug 42089

Bug: 42089

Impact:

Informational

Product:

GemStone/S 64 Bit

Versions:

3.0.1, 3.0, 2.4.5, 2.4.4.8, 2.4.4.7, 2.4.4.6, 2.4.4.5, 2.4.4.4, 2.4.4.3, 2.4.4, 2.4.3, 2.4.2, 2.4.1, 2.4, 2.3.1.6, 2.3.1, 2.3, 2.2.5.4, 2.2.5.3, 2.2.5.2, 2.2.5.1, 2.2.5.x, 2.x

Platform:

AIX on POWER7

Fixed In:

3.1, 2.4.5.1, 2.2.6

Problems with AIX on POWER7

The POWER7 chip provides more aggressive prefetch of data and instructions.
This requires additional memory barriers on atomic updates within GemStone,
to avoid the risk of coherency and audit problems.

These problems are exposed under heavy load on GemStone. It is unlikely
that this bug would cause problems in non-production use.

POWER7 is not a certified platform with currently released GemStone versions,
but documentation for recent releases does not always clearly indicate
problems on POWER7.

Workaround

Do not upgrade production system to a machine running POWER7 when running
a version of GemStone/S 64 Bit that is subject to this bug.