Problems streaming from ReadyNAS by SMB with MPC

Just managed to confirm it seems to be MPC interfering with the transfer speed somehow, copy a folder of series episodes to the desktop, and it runs at a good 35-40MB/s, even spiked to around 45 to begin with. Open MPC, and one of the earlier completed files (It did not seem to slow down with nothing playing) and after a few seconds it slows to a crawl and the average transfer drops, close MPC again (again, bizarrely stopping playback didn't work, it had to be closed) and the transfer speeds up again!

Any, even crazy, ideas greatly appreciated! Because this one has me lost!

Did a little more investigation into this, running task managers networking analysis, and it shows around 50-55% of network utilisation purely on download when streaming, with spikes up to around 80% compared to ~30% when transferring the entire file in a matter of seconds.

Any ideas why streaming a 500meg file over 20-25 minutes would use 60-70MB/s of the network throughput, when transferring the entire file only runs at 30-35? And, if the NAS is capable of transferring at actually, spikes of up to 100MB/s, why doesn't it do that on file transfers? And how can I change this so streaming is effective and if possible, file transfers even faster.

Obviously there is some overhead, but this seems to be a fairly small percentage, just running the maths quickly, 30% of the 125MB/s theoretical possible (1Gb/8) is about 37.5MB/s which makes the overhead around 10%

Also MPC does appear to interfere with file transfers, they run incredibly slowly when MPC is running, but the network utilisation matches this. so during a slow transfer at 500kB/s say, the network utilisation is also very low.

MK999 wrote:
Any ideas why streaming a 500meg file over 20-25 minutes would use 60-70MB/s of the network throughput, when transferring the entire file only runs at 30-35?

Streaming a 500 MB file over 20 minutes takes < 450 KB/s of network throughput. (500*1024*1024)/(20*60) = 437 KB/s. Network spikes would be a different thing - that depends a lot on the protocol used (TCP/UDP), and the details of the buffer management. There are lots of tricks you can play (multiple connections, games with TCP parameters). Another aspect is that MPC is not writing the traffic out to the local disk. Local disk throughput, antivirus and internet security suites wouldn't get in the way.

MK999 wrote:
Obviously there is some overhead, but this seems to be a fairly small percentage, just running the maths quickly, 30% of the 125MB/s theoretical possible (1Gb/8) is about 37.5MB/s which makes the overhead around 10%

I don't follow your math, and am not really sure what overhead you are talking about anyway. Normally overhead is the extra bandwidth used (over the file size). So if it took 550 MBs to transfer 500 MBs of file, then the overhead is 10%.

This is what doesn't make sense, monitoring the network activity, it goes up to 60-70MB/s when MPC streams a file. Stop the streaming and it drops back to 0, it's definitely the streaming causing this traffic, but as you say it should be around 400KB/s not, 140 times that!! This isn't a spike, I can take a picture of the network traffic log, but it's a consistent 60% utilisation of the gigabit network. Unless I've missed something vital in how this works,

The overhead maths comes from an actual transfer, it was about 34MB/s when transferred, and network traffic showed about 30% on average, which is the 37.5MB/s. Anyway the real point is the overhead is quite obviously not 60odd MB/s in the streaming case.

It seems that today streaming is working fine, with about 2% of the gigabit network, much more realistic! Not sure what it was up to before but it seems to have fixed itself!

Seems I'm revisiting this issue again, it's still skipping during playback, although the network usage seems realistic (It's possible I was misreading this before, reading for instance 0.30% as 30% as the scale autochanges with differing load) it's always under 1% which is about right I guess. It was working fine at one point, and all files seemed to stream ok, I'm not sure exactly what if anything has changed again since then, just shutdown/restarts.

I can't find any reference to this issue elsewhere and as far as I'm aware all the equipment should be more than capable of dealing with it all. The only possibility I can see is MPC is somehow putting the playback work onto the NAS but that doesn't seem right and if it did do this I'd expect it to be all over forums etc on google searches.

It's quite a frustrating issue as I have to transfer anything I want to play onto my PC first, and if it's a full series I then need to delete it/clear recycle bin each time, as I only run an SSD on my main PC now and it's getting full.