Page 1 of 1

Can the internal HD be the bottleneck?

PostPosted: Sun Nov 16, 2014 9:21 pm
by parad0xic
I have a somewhat theoretical question.

Supposing that my internal HD is getting slow, or running slowly, if I were to stream from the external HD to my blu-ray player over the network, would that streaming be bottlenecked by the slower internal hard drive, or would it directly stream over the network as its own drive, without needing to pass through the internal drive? In other words, does the movie/USB drive get accessed over the ethernet directly, or does the internal HD mediate the process?

Re: Can the internal HD be the bottleneck?

PostPosted: Sun Nov 16, 2014 11:42 pm
by atc98092
parad0xic wrote:I have a somewhat theoretical question.

Supposing that my internal HD is getting slow, or running slowly, if I were to stream from the external HD to my blu-ray player over the network, would that streaming be bottlenecked by the slower internal hard drive, or would it directly stream over the network as its own drive, without needing to pass through the internal drive? In other words, does the movie/USB drive get accessed over the ethernet directly, or does the internal HD mediate the process?


I'll take a stab at this, but if I'm off base someone please correct me :D

If the file requires transcoding before it is being sent to the display, then yes your internal hard drive will be put to use. If the file does not need transcoding, I'll step out here and say I don't think it does, but in the wild world of computers anything could be possible.

That said, unless your internal hard drive is really, really bad, I doubt it would be a bottleneck for almost any streaming video. Hard drive transfer speeds are measured in megabytes per second, while video streaming is in megabits. A video that streams at 40Mbps (the upper end of an uncompressed HD movie) converts to 5 MBps. Even a poor hard drive can transfer data at 30MBps or more.

Now, if you only have one hard drive in your computer, that means your OS is also using the hard drive at the same time. That will reduce how much thoughtput is available for your video. Again, unless you are using the computer for other tasks while it's streaming, still not likely an issue. But I do have my transcoding folder located on a drive other than my C drive for that reason.

Re: Can the internal HD be the bottleneck?

PostPosted: Tue Nov 25, 2014 6:22 pm
by parad0xic
atc98092 wrote:
parad0xic wrote:
I'll take a stab at this, but if I'm off base someone please correct me :D

If the file requires transcoding before it is being sent to the display, then yes your internal hard drive will be put to use. If the file does not need transcoding, I'll step out here and say I don't think it does, but in the wild world of computers anything could be possible.

That said, unless your internal hard drive is really, really bad, I doubt it would be a bottleneck for almost any streaming video. Hard drive transfer speeds are measured in megabytes per second, while video streaming is in megabits. A video that streams at 40Mbps (the upper end of an uncompressed HD movie) converts to 5 MBps. Even a poor hard drive can transfer data at 30MBps or more.

Now, if you only have one hard drive in your computer, that means your OS is also using the hard drive at the same time. That will reduce how much thoughrut is available for your video. Again, unless you are using the computer for other tasks while it's streaming, still not likely an issue. But I do have my transcoding folder located on a drive other than my C drive for that reason.


No, I never transcode; my CPU is too old I think. Plus my Blu-Ray player is compatible with quite a lot of formats so it's hardly ever a problem. The HDD on my 2008 iMac is dying (which is why I keep all my important files on the external HD). I know my HDD is going bad because its read speed benchmarks (5-15mbps, spiking at 50mbps, very inconsistent) are terribly disproportionate with its write speed benchmarks (consistent 60mbps). Also, S.M.A.R.T. utility says my hard disk is failing.

Because of this idiosyncratic behavior of my HDD, I was wondering if streaming via an external HDD would bypass that. Large 1080p movies sometimes (inconsistently) begin to stutter when I stream them and I'm trying to identify the bottleneck. I don't think it is my network because it's all wired via ethernet (unless the router is crumby?). I tend to think it's the dying HDD, but I was trying to make sure before buying and installing a new drive (I think I'm going to buy a SSD during black Friday.)

Re: Can the internal HD be the bottleneck?

PostPosted: Wed Nov 26, 2014 1:38 am
by atc98092
Well, certainly a possibility. However, be aware that SSD drives are not recommended for use that gets heavy read/write activity. They have a finite number of reads and writes that are far lower than a conventional HD. they work great for your OS partition, but anything that thrashes the drive should not be on an SSD.

I don't know what your finances are, but 500GB hard drives are pretty inexpensive. I am unfamiliar with configuring a Mac, but in Windows you can point both the TEMP folder and the swapfile to a drive other than the OS. This greatly reduces drive activity, and Serviio also has the ability to do any transcoding in a location your specify. Again, not the OS partition if you are running an SSD.

Re: Can the internal HD be the bottleneck?

PostPosted: Wed Nov 26, 2014 5:23 am
by parad0xic
atc98092 wrote:Well, certainly a possibility. However, be aware that SSD drives are not recommended for use that gets heavy read/write activity. They have a finite number of reads and writes that are far lower than a conventional HD. they work great for your OS partition, but anything that thrashes the drive should not be on an SSD.

I don't know what your finances are, but 500GB hard drives are pretty inexpensive. I am unfamiliar with configuring a Mac, but in Windows you can point both the TEMP folder and the swapfile to a drive other than the OS. This greatly reduces drive activity, and Serviio also has the ability to do any transcoding in a location your specify. Again, not the OS partition if you are running an SSD.


Thanks for the tip.

I'm actually putting a 256GB SSD in the main HD bay, and using a SATA/PATA adapter enclosure to swap out my optical drive (which I never use) for a 640GB HDD. That way I'll have dual hard drives; I'll use the small solid state drive for my OS and all my applications, and I'll use the conventional HDD for my media (movies and music).

It's true that the PATA transfer rate is not as fast as the SATA transfer rate – but from what I understand, although the PATA would bottleneck a SSD, it is more than fast enough for a standard conventional 5400 or 7200 RPM HDD.

Re: Can the internal HD be the bottleneck?

PostPosted: Wed Nov 26, 2014 1:46 pm
by atc98092
parad0xic wrote:
Thanks for the tip.

I'm actually putting a 256GB SSD in the main HD bay, and using a SATA/PATA adapter enclosure to swap out my optical drive (which I never use) for a 640GB HDD. That way I'll have dual hard drives; I'll use the small solid state drive for my OS and all my applications, and I'll use the conventional HDD for my media (movies and music).

It's true that the PATA transfer rate is not as fast as the SATA transfer rate – but from what I understand, although the PATA would bottleneck a SSD, it is more than fast enough for a standard conventional 5400 or 7200 RPM HDD.


Yep, the PATA should be fine for a conventional HDD. Although I believe the latest SATA3 drives might be able to max it out, that's usually with burst speeds not sustained. I have (I think) 9 hard drives in my Serviio machine, and 3-4 of them are plugged into an add-on card (ran out of ports :lol: ) which is only SATA2 speed. No issue with streaming multiple movies at the same time.