Mybook live very slow on short reads

I moved many .MKV movies to my new Mybook live (green light).

When I try to play a  11 GB .mkv file with bsplayer from the nas it takes a very long time to start.

It even gives a error message after some time ‘cannot open file’.

I observed with procmon that bsplayer is doing about 300.000 reads with length 1 to determine the end of the movie.

My firewall tells me that data is coming in at 235k / sec. which is ridiculous slow.

When the movie starts playing, bsplayer starts reading in chunks of 65k, which come in at 2 MB/sec.

When a copy the file speed is even about 35 MB second.

Why is Mybook soo slow on short reads ?

It cannot be the network. The switch / router / PC’s are all gigabyte. I have copied the file to an other PC on the same switch in the network and then played the file over the network. I then takes only 1-2 seconds to start.

 I observed with procmon that bsplayer is doing about 300.000 reads with length 1 to determine the end of the movie

It’s the CLIENT (bsplayer) that determines the read length, not the MBL.  

Reading a file at 1 byte per request is why it’s so slow.    That will KILL just about any network performance because 99% of the traffic is overhead.  bsplayer sounds like it is BRUTALLY inefficient.  

If bsplayer is also doing sequential 1byte reads on a PC, then presumably the PC is precaching that information which will increase performance somewhat, but not much, because it’d be easily CPU-bound.

35 megabits per second copy seems pretty slow, too.   I can get 220 to 250 megabits per second between my PC and MBL…

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Sorry about the confusion. I ment megabytes instead of megabits.

I corrected it in MB.

However, 1 byte reads are ONLY slow when accessing the Mybook live.

The same file on a share on an other PC reads at lease 60x faster.

The network, as you state, is the same so that is not causing the bottleneck.

It is specific when accesing the Mybook live.

Ok, after 6 hours of experimenting I think I found a bug.

The files are placed in a user defined share called ‘films’.

If I place the .mkv in public\shared video Bsplayer loads them in 1-2 seconds instead of 90 seconds.

Beats me why there is a difference in an user defined share and the public one. :neutral_face: