Weird Speed loss on transfers?

[Carnagerover]

Hi all,

I have the following equipment;

TP-Link Archer C7 Router < Netgear GS108T Switch - Via CAT5e Cable

I am using 7 out of 8 ports on the Netgear, 5 ports are running gigabit and 2 are running 100mbps. There is currently only one device plugged into the Archer that is used for Internet TV.

My question is that at times from my PC which is a desktop gaming machine with fast hard drives and a gigabit connection I am seeing speeds drops.

Normally transfers from my PC to my NAS are at around 64-65MBps and then reads from the NAS which is a Zyxel NSA 325 are at 100MBps, however at the moment I am seeing reads of around 80MBps and writes of around 50MBps.

Nothing has changed on the network and nothing additional is running on the NAS, sometimes it comes back briefly but I'm not experienced enough to know what is bogging it down. Even copying to and from a fast SSD doesn't steady the rate.

I guess I am just wondering what the problem/Bottleneck is?

 

[azazel1024]

Are they bog standard HDDs in the NAS and not SSDs?

At a guess, disk fragmentation on the PC or the NAS.

Don't trust windows to tell you the true state of fragmentation of a drive. On my server (win 8 box) I can run the disk analyzer and it can tell me my RAID0 array is 0 percent fragmented, but I'll see file transfer from the server go from 210MB/sec down to 30-40MB/sec after a couple of seconds. I can then cancel it, check the drive analyzer, 0% fragmented. Anaylze again, 0% fragmented. Run disk optimizer and it'll chew away for a minute or two deframenting and then 10-15 minutes consolidating, punch up the transfer again and it sails along at 210+MB/sec again (I have two GbE links running in SMB Multichannel).

Putty for some reason seems to fragment the hell out of disk writes when copying over FTP. I don't know why, I don't know how, but it seems the inevitable result of anything I copy over FTP using Putty. The first bit of a file will transfer fine for 200-500MBs, but then it bogs WAY down unless I've optimized/defragged the array since I pulled down the file over Putty, in which case it just sails along.

It is only really putty that does it, that or tons of disk clean up combined with writing a lot of stuff back to the array can clog it up and need defragging, but I don't see the same level of slow down.