Periodical rise of CPU load

Yura Dinkevich

Hello,

I'm running video D1 capturing on DM365 under Linux (simple QBUF/DQBUF loop on v4l device, not through DMAI). The 'top' shows that the process takes about 0% of CPU load. But each 4.5 minutes CPU load of the process rises up to 25% for 3-5 seconds.

During test every possible non-related task or service are disabled.

When testing it on Kernels 2.6.18, 2.6.32, 2.6.37, we get the same results.

What can be the cause?

Thanks in advance.

over 14 years ago

0 Mike Whittaker over 13 years ago

Intellectual 410 points

Could it be caused by memory fragmentation ? Are your buffers allocated anew each time or do you hold them in a pool, and re-use them ?

0 Yura Dinkevich over 13 years ago in reply to Mike Whittaker

Prodigy 40 points

No, we have only static allocation of the pools.

0 Santoshkumar Pattar over 13 years ago in reply to Yura Dinkevich

Intellectual 515 points

Hi Yura,

I am also seeing the same behaviour with video capture driver (DQBUF and QBUF only) on 2.6.18 MVL kernel on DM6467. Did you find solution for this issue? If so, please share.

This is also posted at http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/99/p/32127/683715.aspx#683715 However, no one has replied with the solution.

Regards,

Santosh

0 Santoshkumar Pattar over 13 years ago in reply to Santoshkumar Pattar

Intellectual 515 points

Hi All,

One of the solution is to use the driver in non-blocking mode - posted at http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/99/p/32127/684690.aspx#684690

Regards,

Santosh

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Periodical rise of CPU load