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Ubuntu Download Speeds Beat Windows XP's
narramissic writes "Doing a download speed test of his Time Warner cable connection, James Gaskin discovered something odd, something that he is quick to note isn't a rigorous benchmarked lab test. The discovery: His Ubuntu machine 'returned a rating from the Bandwidth.com test of 22-25mbps over several tests' while the same test done from a Windows XP PC returned a rating of 12-14mbps. The two computers used in the test are 'almost identical: both off-lease Compaq small form factor D515s, part of the very popular corporate desktop D500 family. Both have Pentium 4 processors running at 2GHz. The Ubuntu machine has 768MB of RAM, while the XP box has only 512MB of RAM. Both run Firefox 3 as their browser.' Gaskin's question: Can a little extra RAM make that much difference in Internet download speeds or does Ubuntu handles networking that much faster than Windows XP?"
Anecdotally, I have also noticed that Ubuntu boxes tend to hog bandwidth, as compared to an XP box at home. When someone on the home LAN starts downloading or streaming something from a linux box, everyone else notices it immediately. The XP box is (inadvertently?) more polite about it. Still, if you're the only one pulling in the big byte loads, faster is definitely better.
I've read reports stating that Ubuntu's Java machine is faster than Windows'. Some of those speed test sites use Java to implement the test. This is probably the best explanation.
Who gets 22mbps from a cable modem?
People who have cable service that gives them 22mbps? Such a thing isn't that extraordinary.
possibly due to tcp window scaling
http://en.wikipedia.org/wiki/TCP_window_scale_option
ubuntu does it. Windows XP does not.
The TCP window scale option is an option to increase the TCP receive window size above its maximum value of 65,536 bytes. This TCP option, along with several others, is defined in IETF RFC 1323 which deals with Long-Fat networks, or LFN.
-rant mode, how I found out about it.
The secure side of the Presidents Choice banking web site is royally hosed by a machine that tries to use tcp window scaling. Why can't a web service provider, one that should be extra careful about security understand a standard concept.
Unless you're running on an old 4200rpm laptop drive, write speed shouldn't be a problem compared to internet speeds. 22mbps is only 2.75MBps, which pretty much any relatively modern drive can do, even near-full and fragmented to hell.
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Yeah people keep claiming this with no real data to prove it up so it's about as worthless as the shit that the article claims. My parents have an XP box with only 512 megs of RAM and it easily maxes out at the 22mbps that they have. And that's with a half dozen apps open and at least 8 things running in the background on the systray. Seriously, the extra 256 megs of RAM isn't going to give you magically 2x the bandwidth.
Unless you're running on an old 4200rpm laptop drive, write speed shouldn't be a problem compared to internet speeds. 22mbps is only 2.75MBps, which pretty much any relatively modern drive can do, even near-full and fragmented to hell.
It is not an issue of write speed. The CPU AND the drive are busy at the same time. If swapping weren't such a nuisance demand for RAM would drop dramatically.
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
Product A in lab tests always performs over 100% better/faster than product B.
Product B in normal use always performs over 100% better/faster than product A.
Which are you going to want to use? Perhaps product A is designed to max the test, while product B is designed to handle varying conditions.
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I've spend a lot of time looking at this type of problem. I had a customer that wanted to transfer data at greater then 10 mbps across the internet, across the country. Lets just say with windows this is impossible.
The problem has to do with TCP algorithms. I found the ones in windows are optimized for common cases. Linux has multiple TCP/IP algorithms you can choose from. Most are significantly better the one used in windows.
The "problem" with TCP is it has to assume that packet loss equals network congestion. This is a good thing for an over-loaded network link. As the link fills up, it starts dropping packets. As the computers on each end of a TCP connection see this packet loss, they start "Backing off". They slow down their transmission rates until the packet loss is gone. In most cases they back way off, and then slowly increase the speed until they start seeing a little packet loss. The methods they use to determine what is congestion, how much they slow down, and how they recover from it greatly effects total usable bandwidth.
The bottom line: TCP Algorithms greatly effect transfer speed, and no algorithm is good for every situation. Linux gives you flexibility in this area (And by default uses a better one), and windows gives you zero.
To test raw bandwidth, you have to saturate a link with UDP data, and count how much data is received. This is pretty pointless as its not the useable bandwidth, but it does tell you the "raw" potential. The problem is the "raw" potential can be subverted by a small amount of packet loss.
Dell XPS M1530 Intel Core 2 Duo (2.16ghz) 3 gigs RAM Dual Booting Windows Vista Home Premium AND Ubuntu 8.10 http://www.bandwidth.com/tools/speedTest/ Six tests per OS. Vista: Download/Upload 7616/2795 7865/2724 6407/2755 10050/2800 12320/3925 15854/2905 Ubuntu: Download/Upload 12939/5897 8849/12122 15373/18646 20040/17093 8461/14969 17885/13807
"More similar" is such a fascinating phrase. Regardless (or should that be irregardles?), Linux has better algorithms for TCP control - and a much, much wider range. If Web100 is installed (not, in this case, as it's a default install), it is also auto-tuning. Disk access is also important, and again Linux has a superior range of choices for block I/O handling. Whether comparable choices are superior on one OS or another is a different question, because again this is a default install and so all we care about is whether the default choice is a superior algorithm. Then, there is the matter of context switch overhead. Network I/O and disk I/O both use the kernel, but the application would be in user-space, so you've lots of context switches to ferry data between interfaces. (Which is a stupid design, and there is hardware out that avoids it, but if you're using an x86 anyway, why use efficient hardware?) My understanding is that Windows context switches are much more expensive than those in Linux.
So, if you add up all of these factors, it is entirely possible that the choice of OS alone could indeed make a difference as large as is being reported, and that with a bit of tweaking, it should be possible to achieve vastly superior performance yet.
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256 will make a big difference if it keeps your machine from thrashing the hd via the swapfile. A standard XP install +virus +GoogleSearch +Msoffice Quick Start +OtherBloatware will almost completely soak up that 512. Windows essentially freezes while it reads/writes to swap. A better test would be to boot a Ubuntu live cd and see how well the identical hardware performs in the network test.
He should remove 256mb of ram from the Ubuntu box and try again...
Infact, he should dual boot both machines and run his benchmarks again.
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Well, even if the hardware was the same, I'd blame the drivers. On Windows, lots of networking equipment has crummy drivers coded by companies that really don't care that work, but with much higher latency and bandwidth than the hardware is capable of.
I actually get better performance off the USB wifi card in my desktop than the PCI one built-in, because the PCI one has lousy drivers and the USB one has good drivers.
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I know Comcast has a thing (Powerboost) where it gives you double download speeds for the first x minutes of a download. Could that be at work here?
Maybe because the vast majority of Windows users run XP and the vast majority of Ubuntu users run recent versions?
The one thing many scientifically-minded people fail to take away from their college course in benchmarking is that a rigorously scientific comparison is often not the best comparison. Who cares what the latest and greatest, optimally tuned, super fair, scientific benchmark says if an average user experience is far different?
This space intentionally left blank.
Fine, what is this then:
Windows (Cygwin):
$ ping -n 20 www.google.com
Pinging www.l.google.com [74.125.39.147] with 32 bytes of data:
Reply from 74.125.39.147: bytes=32 time=12ms TTL=245
[...]
Ping statistics for 74.125.39.147:
Packets: Sent = 20, Received = 20, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds: Minimum = 11ms, Maximum = 41ms, Average = 16ms
Ubuntu:
lukas@9a:~$ ping www.google.com
PING www.l.google.com (74.125.39.147) 56(84) bytes of data.
64 bytes from fx-in-f147.google.com (74.125.39.147): icmp_seq=1 ttl=245 time=15.3 ms
--- www.l.google.com ping statistics ---
22 packets transmitted, 1 received, 95% packet loss, time 21003ms
rtt min/avg/max/mdev = 15.321/15.321/15.321/0.000 ms
Happens on my network no matter what I change - cables or notebooks, Vista runs ok, Ubuntu sucks big time. The only non-standard thing is that I have wired connection with manual IP address (connected by Linux based Asus router).
lukas@9a:~$ lspci | grep Eth
00:19.0 Ethernet controller: Intel Corporation 82567LM Gigabit Network Connection (rev 03)
This story doesn't surprise me at all. I am a developer for next generation cable equipment, and we have also seen problems with Windows XP mysteriously and severely limiting our downspeed tests (to about half of our expected speed). We spent a lot of time banging our heads against our own cable modem firmware and the network config on the laptop before we finally figured out that Windows XP was the root cause of the limited bandwidth. Not much more we could do to figure out exactly why since Windows isn't open source. Maybe we should have installed Ubuntu on the laptop. Why would MS need to make their products work well? The majority of Windows users don't know enough to measure how much it sucks anyway.
XP's TCP/IP stack is much the same as NT has been using for quite a while. It takes ages to ramp up the TCP window size. It makes for terrible results on "speed tests" unless the test is quite a long download.
Vista is much more aggressive in increasing the receive window.
Run a throughput monitor of some sort while performing the test - preferably one that graphs throughput against time.
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winXP x64 sp2:
ubuntu 8.10 x64:
huh, weird.
On my dual-boot T61 wifi is *infinitely* faster in Kubuntu than in windows xp... because at some point for absolutely no reason I've been able to figure out (and I've tried) the Windows wifi drivers suddnely quit being able to connect to my access point many months ago... while Linux's drivers in Kubuntu continue to work just fine.
More similar sounds odd but certainly seems to be valid language to me. If item a and b have similarities they are similar, if item c has more similarities to a than b than it could be said be more similar to a while b is less similar to a.
'irregardless'
Nonsensical as it may seem irregardless is certainly a word now. Usage and adoption and not pedants define language.
What it doesn't account for is the upload speed, which were very consistent throughout this silly test.
Probably because of this.