APT_BufferOperator

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pavan_test
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APT_BufferOperator

Post by pavan_test »

Hi All,

I have a problem in while running a data stage job in version 8x. os is aix.

buffer(11),0: APT_BufferOperator warning: currentWriteTime <= lastWriteTime, 1216910062.65395 1216910103.79412
buffer(0),1: APT_BufferOperator warning: currentWriteTime <= lastWriteTime, 1216910062.66623 1216910103.90485
Issuing abort after 50 warnings logged.(this is fatal error) job aborts here.

can anyone please tell me what is this error and why it this happenning in my job.

thanks
Mark
miwinter
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Post by miwinter »

Hi,

I think your 'fatal' is coming from the job breaching it's set warnings limit. As for the nature of the warning itself, it's obviously coming from one of the buffers it's added to a stage or other - are any set to anything other than default?

You should be able to identify the related buffers from the score.
Mark Winter
<i>Nothing appeases a troubled mind more than <b>good</b> music</i>
ray.wurlod
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Post by ray.wurlod »

Does this job run through midnight?
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benghiat99
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Re: APT_BufferOperator

Post by benghiat99 »

This is from IBM support:
Checked with engineering. In this case PX buffer operators are making calls to gettimeofday to compute timeouts that are dependent on the rate of data flow. There are many variables that can effect when and how often these calls are made, so it isn't surprising that the warnings are somewhat transient.

This is part of AIX manpage:
man gettimeofday

If a recent adjtime subroutine call is causing the clock to be adjusted
backwards, it is possible that two closely spaced gettimeofday calls will
observe that time has moved backwards. You can set the GETTOD_ADJ_MONOTONIC
environment value to cause the returned value to never decrease. After this
environment variable is set, the returned value briefly remains constant as
necessary to always report a nondecreasing time of day. This extra
processing adds significant pathlength to gettimeofday. Although any
setting of this environment variable requires this extra processing,
setting it to 1 is recommended for future compatibility.

This solved our buffer message Problem, good luck
madhavig
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Post by madhavig »

Hi,

I am also facing the same issue.

Could you please let me know how can i set this environment variable GETTOD_ADJ_MONOTONIC to a constant value? is it an inbuilt variable or user defined variable and how can use this variable in the datastage job?

Thanks & Regards,
Datastage developer.
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