Hi all,
NTDEV seems to want me to make a new thread due to age of the previous threads…
I’m experiencing the same failure as described by several other posters ( http://www.osronline.com/showthread.cfm?link=197143 and http://www.osronline.com/showthread.cfm?link=175074 ), which is that after several hundred iterations of allocating/deallocating 1394 bandwidth we will get an STATUS_ACCESS_DENIED error from REQUEST_ISOCH_FREE_BANDWIDTH. I wanted to see if anybody has discovered any further details about this or any possible workarounds (besides switching to the older driver which limits S800 speeds).
Thanks,
Eric Gross
Furthermore, when debugging this issue, I also noticed another peculiar issue that may or may not be related to the above problem.
On a system with 2GB of RAM, when I test the above issue with an allocate/deallocate loop, I just encounter the issue mentioned above. If I add another 2GB of RAM to the system to make it 4GB, while I am running the looping test above I see that the “in use” physical memory keeps growing by about 1.5MB per iteration. It is not charged to the process or the kernel memory. If I restart the OHCI driver the memory is restored. It is interesting that this apparent leak is only present when I have 4GB of memory or more present. Could the OHCI driver be allocating bounce buffers of some sort that are not freed (even though I believe we always give the OHCI driver 32-bit-DMAable memory)? I do see some apparent correlation between the leaked memory per iteration and how large of buffers are being transferred…
Eric Gross
As to my knowledge, this has been recognized as being
an issue with the Win 7 1394 stack. I don’t know,
whether this will be hotfixed.
Regards, Udo Lenz, CCD Videometrie
On Fri, 18 Feb 2011 17:03:22 -0500 (EST), eric.gross@ni.com wrote:
Hi all,
NTDEV seems to want me to make a new thread due to age of the previous threads…
I’m experiencing the same failure as described by several other posters ( http://www.osronline.com/showthread.cfm?link=197143 and http://www.osronline.com/showthread.cfm?link=175074 ), which is that after several hundred iterations of allocating/deallocating 1394 bandwidth we will get an STATUS_ACCESS_DENIED error from REQUEST_ISOCH_FREE_BANDWIDTH. I wanted to see if anybody has discovered any further details about this or any possible workarounds (besides switching to the older driver which limits S800 speeds).
Thanks,
Eric Gross