10 Gigabit

[jacob_samd]

Greetings, I am wondering if I need a switch to connect my desktop to my nas via sfp+. I have it currently connected to my nas and sometimes it works at 10 gigabit speeds and sometimes not. I am not sure if I need a switch to make it work or if I have something else not working. It is connected by sfp+ cable and the same network card in each computer. Thanks

[mtz_federico]

9 hours ago, jacob_samd said:

Greetings, I am wondering if I need a switch to connect my desktop to my nas via sfp+. I have it currently connected to my nas and sometimes it works at 10 gigabit speeds and sometimes not. I am not sure if I need a switch to make it work or if I have something else not working. It is connected by sfp+ cable and the same network card in each computer. Thanks

you don't need a switch. the speed variations can be caused by something else using the CPU or HDD/SSD while you are moving files.

smaller files also won't get to high speeds

[jacob_samd]

10 hours ago, mtz_federico said:

you don't need a switch. the speed variations can be caused by something else using the CPU or HDD/SSD while you are moving files.

smaller files also won't get to high speeds

Thanks for the information. It just seems weird that sometimes it transfers big files super fast and sometimes it seems super slow transferring the same file. My desktop is a 2800x I believe and I have an ssd in there. I’m guess hiccup may be with my naps as it is only a pentimento cpu. I do have a samsung m.2 cache though so that seems to be helpful.

 

[sphbecker]

13 hours ago, jacob_samd said:

Thanks for the information. It just seems weird that sometimes it transfers big files super fast and sometimes it seems super slow transferring the same file. My desktop is a 2800x I believe and I have an ssd in there. I’m guess hiccup may be with my naps as it is only a pentimento cpu. I do have a samsung m.2 cache though so that seems to be helpful.

 

10 Gig is VERY fast! Any number of conditions going on with your computer or NAS could cause you to not reach those speeds. If the NAS has mechanical drives, then they will not be able to keep up, no question about it, you would only get anything close to 10 Gig if you are copying something that has already been cached. Also keep in mind that modern SSDs use multi layered NAND, which allows for higher density but hurts performance. All SSDs have a section of single layer that is used for fast writes and then later moved into multi-layer storage. If you use all of the single layer capacity, you will see a very notable drop in SSD performance. The Samsung Pro SSDs have a much larger section of single layer, but the standard EVO devices only give you a few GB. Once it is gone, performance will slow until the SSD has a chance to move that data. It actually works pretty well for normal use, but could explain a drop if you are trying to do a test by copying huge files.

 

If you want to test the network link, you need to use something like iperf (if your NAS supports it). Copying files has so many other pieces in the mix that you will probably never max out the 10 Gig link (at least not with today's consumer grade hardware).

 

That is not to say 10 Gig is a waste. You probably are getting well above 1 Gig, just maybe not the full 10.

[sphbecker]

1 hour ago, trueCABLE said:

• Windows...ugh...the networking stack is not exactly designed for full and stable 10G speed.  Linux is.

I do not agree with this statement. Neither network stack was designed with 10G in mind. They are both designed to operate efficiently with little overhead and have no problem achieving both the bit/sec and pps its hardware is designed for. If you want to say that Windows is very chatty and sends out tons of wasteful broadcast packets, that is a fair complaint, but its network stack is fine.

[trueCABLE]

1 hour ago, sphbecker said:

I do not agree with this statement. Neither network stack was designed with 10G in mind. They are both designed to operate efficiently with little overhead and have no problem achieving both the bit/sec and pps its hardware is designed for. If you want to say that Windows is very chatty and sends out tons of wasteful broadcast packets, that is a fair complaint, but its network stack is fine.

Sorry you do not agree, but I have extensive testing that shows otherwise.  There are no issues with achieving 10G bandwidth as expected on a single TCP stream with iperf in Linux.  Very easy to do, with no gyrations.  Try that with a single TCP stream in Windows 10, for example...even when you are disconnected from the Internet.  This is RAM to RAM mind you...no other bottlenecks.  Read the white paper thoroughly and see what I mean.