Informix

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Probably not related but wasn't FC4 the first release that allowed ontape to use differing UID/GID combinations ?

Cheers

Paul

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Seeing more of the same behavior.  Engine hung with "CKPT REQ".

Do we following messages in the log have any explanation other than abnormal behavior by the engine (physical log is sized at 8 GB on this instance):

20:30:06  Performance Advisory: Unable to extend Physical Log.

20:30:06   Results: Attempt to extend physical log dbspace FAILED.

20:30:06   Action: Please notify IBM Informix Technical Support.

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Seeing more of the same behavior.  Engine hung with "CKPT REQ".

Do we following messages in the log have any explanation other than abnormal behavior by the engine (physical log is sized at 8 GB on this instance):

20:30:06  Performance Advisory: Unable to extend Physical Log.

20:30:06   Results: Attempt to extend physical log dbspace FAILED.

20:30:06   Action: Please notify IBM Informix Technical Support.

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Yes but:

1. Why is it trying to extend the physical log on its own in the first place?  
2. If it decides to extend it then why is it unable – the 8 GB physical log is in its own dedicated 24 GB dbspace with 16 GB more space available.
3. Is all this because of the  wonderful autonomic features that are enabled on this engine – AUTO_CKPTS etc. are set to 1.  Do you think this problem will go away if those are zero?

Thank you,

Hal

Seeing more of the same behavior.  Engine hung with "CKPT REQ".

Do we following messages in the log have any explanation other than abnormal behavior by the engine (physical log is sized at 8 GB on this instance):

20:30:06  Performance Advisory: Unable to extend Physical Log.

20:30:06   Results: Attempt to extend physical log dbspace FAILED.

20:30:06   Action: Please notify IBM Informix Technical Support.

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Yes but:

1. Why is it trying to extend the physical log on its own in the first place?  
2. If it decides to extend it then why is it unable – the 8 GB physical log is in its own dedicated 24 GB dbspace with 16 GB more space available.
3. Is all this because of the  wonderful autonomic features that are enabled on this engine – AUTO_CKPTS etc. are set to 1.  Do you think this problem will go away if those are zero?

Thank you,

Hal

Seeing more of the same behavior.  Engine hung with "CKPT REQ".

Do we following messages in the log have any explanation other than abnormal behavior by the engine (physical log is sized at 8 GB on this instance):

20:30:06  Performance Advisory: Unable to extend Physical Log.

20:30:06   Results: Attempt to extend physical log dbspace FAILED.

20:30:06   Action: Please notify IBM Informix Technical Support.

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Yes but:

1. Why is it trying to extend the physical log on its own in the first place?  
2. If it decides to extend it then why is it unable – the 8 GB physical log is in its own dedicated 24 GB dbspace with 16 GB more space available.
3. Is all this because of the  wonderful autonomic features that are enabled on this engine – AUTO_CKPTS etc. are set to 1.  Do you think this problem will go away if those are zero?

Thank you,

Hal

Seeing more of the same behavior.  Engine hung with "CKPT REQ".

Do we following messages in the log have any explanation other than abnormal behavior by the engine (physical log is sized at 8 GB on this instance):

20:30:06  Performance Advisory: Unable to extend Physical Log.

20:30:06   Results: Attempt to extend physical log dbspace FAILED.

20:30:06   Action: Please notify IBM Informix Technical Support.

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.

Yes but:

1. Why is it trying to extend the physical log on its own in the first place?  
2. If it decides to extend it then why is it unable – the 8 GB physical log is in its own dedicated 24 GB dbspace with 16 GB more space available.
3. Is all this because of the  wonderful autonomic features that are enabled on this engine – AUTO_CKPTS etc. are set to 1.  Do you think this problem will go away if those are zero?

Thank you,

Hal

Seeing more of the same behavior.  Engine hung with "CKPT REQ".

Do we following messages in the log have any explanation other than abnormal behavior by the engine (physical log is sized at 8 GB on this instance):

20:30:06  Performance Advisory: Unable to extend Physical Log.

20:30:06   Results: Attempt to extend physical log dbspace FAILED.

20:30:06   Action: Please notify IBM Informix Technical Support.

Hello everyone,

Is anyone aware of a bug or have come across unusual behavior with version 12.10.FC4 engine on Linux where, usually when an ontape is running, sometimes the shared memory usage jumps exponentially, sometimes physical log keeps growing exponentially?

These issues occurred on several occasions on this particular server where:

It crashed on multiple occasions due to shared memory growing to the max allowed by the operating system (that one has been addressed largely by a better configuration approach),

Physical log grew to 75% full and got "stuck" there on a checkpoint required status, holding up all updates/inserts/deletes.  This particular physical log is sized sufficiently in my opinion, about the same size as the total buffer pool – it is not tiny at all.

These problem scenarios seem to present themselves when ontape level zero archive starts, but not every time ontape starts of course.  There does not seem to be any "major" application processes starting/running at the same time.

Very problematic behavior I have not seen in any other setup I worked with over the years.  Trying to decide if an upgrade is in order (there is resistance to it) but if so, need some concrete proof.

Thank you,

Hal Maner

M Systems International, Inc.