2015-04-28, 05:21 AM
FYI: I upgraded to NPVR 3.4.8 over the weekend, but I don't know if that makes a difference.
Tonight I had several shows recording at once from a combination of regular HDHRs (ATSC via BDA/NDigitalHost) and HDHR Primes (CableCard via NRecord). And I was watching a show recorded before on the NMT. Several times I noticed that my playback would hang for several seconds, so I began to investigate.
What I found was that when my playback would hang, there were HUGE (48-65 MB/s) writes going to the recording disk (a local SATA drive) for one of the shows being recorded from an HDHR Prime tuner. So I began to watch the physical disk activity on the recording drive more carefully. What I found was that for the shows being recorded from the ATSC HDHR, there would be pretty consistent writes (1.6-1.8 MB/s) to the .ts file and (about 2 KB/s) to the timing.info file. And for shows being recorded from the HDHR Prime, there would be periods of many minutes between writes to the .ts file and when they did occur, they were these huge 48-65 MB/s writes for about 30 seconds each that would temporarily block out the reads for the playback. (Upon more investigation, I am wondering if these may not be writing out to the physical disk until the recording completes and then writing the entire file at once!)
These recordings are all going to the same physical disk, so the Windows caching, etc. should be the same. Which leads me to think that somehow NPVR is doing something differently in the writing of the files between the ones written by NDigitalHost and the ones written by NRecord. Any ideas, sub?
Tonight I had several shows recording at once from a combination of regular HDHRs (ATSC via BDA/NDigitalHost) and HDHR Primes (CableCard via NRecord). And I was watching a show recorded before on the NMT. Several times I noticed that my playback would hang for several seconds, so I began to investigate.
What I found was that when my playback would hang, there were HUGE (48-65 MB/s) writes going to the recording disk (a local SATA drive) for one of the shows being recorded from an HDHR Prime tuner. So I began to watch the physical disk activity on the recording drive more carefully. What I found was that for the shows being recorded from the ATSC HDHR, there would be pretty consistent writes (1.6-1.8 MB/s) to the .ts file and (about 2 KB/s) to the timing.info file. And for shows being recorded from the HDHR Prime, there would be periods of many minutes between writes to the .ts file and when they did occur, they were these huge 48-65 MB/s writes for about 30 seconds each that would temporarily block out the reads for the playback. (Upon more investigation, I am wondering if these may not be writing out to the physical disk until the recording completes and then writing the entire file at once!)
These recordings are all going to the same physical disk, so the Windows caching, etc. should be the same. Which leads me to think that somehow NPVR is doing something differently in the writing of the files between the ones written by NDigitalHost and the ones written by NRecord. Any ideas, sub?
