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I’m stuck and can't figure out how to get my speeds any faster, or figure out why my transfer speed is so slow between PC’s compared to from the Internet.
Please be aware when reading this that because of how hardware reports speeds, and how software and OSes report speeds, I’m using both Bps (Bytes per second) and bps (bit per second).
- 8bps = 1Bps
- 8mbps = 1MBps, and so on.
Here’s my setup:
File Server:
- OS: Lubuntu
- RAM: 2GB
- Wired Ethernet 100
- Download speeds from speedtest.com is ~5MBps
- Actual download from high seed torrent ~3-3.5MBps
- Hard drive speed ~60MBps
Client:
- OS: Ubuntu
- RAM: 16GB
- Wi-Fi B/G/N (Connected at 72.2Mbps, 9MBps)
- Download speeds from speedtest.com is ~3MBps
- Actual download from high seed torrent ~2-2.5MBps
- Hard drive speed ~400MBps
Router: (Server connected via wired Ethernet, client over WiFi)
- Wireless B/G/N with 4x 1G Ethernet ports
I’ve tried several different connections, and the best speed I’m getting according to iperf
is ~1.3MBps in either direction. I've tried SMB, FTP, etc, and NFS gets me the best speeds for file transfer speeds according to the system monitor.
Actual file transfers however from client to server in either direction fluctuate anywhere between 120-200 KBps.
Both systems during transfer have 99% idle CPU time. The client is only using 700MB/16GB RAM. The server is only using 100MB/2GB RAM. HDD activity is very low compared to doing local file operations.
netstat
, nfsstat
, etc are not reporting any dropped packets or timeouts.
I’ve eliminated possible bottlenecks like CPU, RAM, HDD. So how can it be that I’m getting so much more speed from the Internet compared to within my LAN?
UPDATE
After a couple of days, and not really changing anything, I’m now all of a sudden getting over 20Mbps. The transfer speeds of 2-3MBps are much better. However, my slowest link here is the WiFi at 72.2Mbps which is 9MBps. Taking out any overhead and whatnot, I should still be able to achieve 7-8MBps but I'm not even at half of that yet.
Transfer speeds from Client to Server are about 2-3MBps. But Transfer speeds from Server to Client are about 5-6MBps.
Why are they different?
How are the two PC's attached to each other? If you replace all network infrastructure between the two PCs with a cross-over network cable (a straight-through will probably work if you have Gb adapters), are the transfer speeds between the PCs as expected? – Ƭᴇcʜιᴇ007 – 2016-06-24T15:49:34.550
@Ƭᴇcʜιᴇ007 Via a wired and wireless router (updated question). Haven't tested directly connected to eachother but the issue is that WAN is much faster than LAN. – Dorian – 2016-06-24T16:10:01.507
My main suspect is your router's ability to process LAN traffic, hence why I suggested eliminating it. If you haven't tried a completely different router (or a direct cross-over cable connection), then you have not ruled it out. – Ƭᴇcʜιᴇ007 – 2016-06-24T16:32:06.177
@Ƭᴇcʜιᴇ007 I'll give it a shot. – Dorian – 2016-06-24T16:58:07.843
@Ƭᴇcʜιᴇ007 So, tried to plug them into eachother, and my client laptop actually doesn't have an ethernet port at all lol. So much for that. But, now it's been a few days, I've done nothing different, and I'm getting between 2-3 MBps transfers speeds. It's better, but on my 72Mbps WiFi, that's a max of 9MBps so I should be able to get at least 7-8MBps. – Dorian – 2016-06-25T17:00:42.737
What is the exact make and model of the router? Also, you state “…and my client laptop actually doesn't have an ethernet port at all…” So it’s unclear to me what you are attempting to fix: Are you saying that Internet speeds regardless of the connection being wired or WiFi are faster than connection between the two servers—going through the router—via WiFi? This all sounds like a case of either the router choking or—more likely—the Ethernet connection between the server and router being problematic. The physical cable itself could be damaged so try replacing that. – JakeGould – 2016-06-25T17:33:42.070
Router is Actiontec T1200H supplied by my ISP. Yes internet speeds were faster on both computers when compared to speeds between them. But I've also updated my question at the bottom on how its behaving now, and how Server->Client is faster than Client->Server which I find odd. – Dorian – 2016-06-25T17:41:11.837
Network speeds are measured in megabits/sec (10^6's of bits per second). Disk and File I/O speeds are typically measured and reported in MebiBytes/sec (2^20's of 8-bit Bytes per second, abbreviated "MiB" by people who care). You can't convert between megabits and MebiBytes by dividing by 8. It's closer to 8.4. If you check the speed of a file download or file read/write tool, it almost certainly reports in MebiBytes/sec, not SI mega (even though most tools still misleadingly call it "MB" instead of "MiB"). You'd do well to correct your conversions.
– Spiff – 2016-06-27T18:25:32.547What does "iperf…using NFS" mean? The
iperf
I'm familiar with is a pure TCP or UDP performance tool, not a filesystem protocol performance tool. It doesn't read/write files over NFS or SMB or anything. – Spiff – 2016-06-27T18:30:41.437@Spiff Thanks for that but I'm not concerned about exact speeds, just in general. Converting all my bps to Bps yeilds the same difference ratio. 9MBps is 8.6MebiBytes/s, and that 200k/s difference is not what I'm worried about. My concern is that one direction is twice as fast as the other, regardless of what metric I use. – Dorian – 2016-06-27T18:31:37.183
Wi-Fi overhead is worse than you're adjusting for. TCP throughput over B/G is only about 50% efficient. 802.11n's frame aggregation can boost that to 60-80% (let's call it 70%). – Spiff – 2016-06-27T18:32:59.580
@Spiff You're right, I'm not using the right tool there. My notes on paper are a mess according to what I've used to test what in the past. I meant system performance tool (gnome-system-monitor). – Dorian – 2016-06-27T18:33:45.633
@Spiff I know the WiFi overhead is heavy, but I'm not getting timeouts or dropped packets. Even with almost 100% link state and hardly any DB loss being close to the router, I'm getting much faster receives than sends from the WiFi laptop. – Dorian – 2016-06-27T18:36:42.177