Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Obviously it's just one factor in the mix, but if I host a site here in the UK knowing that the majority of my users are in the U.S., how much weight should I give concerns about access speed for those users? (Currently ~70% U.S. users, ~20% UK, remainder are all over.) Trans-Atlantic hops used to be a bit of a big deal, but is it really much of a factor in today's world?

Again, I recognise this is only one factor in the overall mix, just looking to see how much weight the community thinks I should give it.

(Before you suggest it, using one of the big CDNs/clouds -- Amazon s3+ec2, Google AppEngine, etc. -- isn't an option at the moment.)

EDIT: All answers welcome; any stories of direct experience with this would be especially helpful.

share|improve this question
On the East Coast of the US, I often find d/l from UK and Europe file sites to be faster than West Coast sites. So, the answer is "depends". If you get a US server, I suggest getting one colo'd in the Western US. – kmarsh Oct 5 '09 at 13:16
If 70% of your users are in the US why wouldn't you put/keep the server in the US? – Ryan Oct 5 '09 at 14:09
As I say, it's part of the overall mix. Looking around, I'm finding some very good hosting companies in the UK now, and for the first time in my experience they're also price- and feature-competitive. Rather than disregarding them out-of-hand, I thought I'd ask the question. – T.J. Crowder Oct 5 '09 at 14:26
I agree with @kmarsh, but to answer the "it depends" question, you have to measure and test, then measure and test again! – Tom H Mar 24 '12 at 15:08
up vote 2 down vote accepted

There used to be significant issues with both latency and throughput with transatlantic links. These days though the bandwidth available (assuming your ISP/host has decent peering arrangements) is such that throughput isn't really an issue in most cases.

Latency can still be an issue, but only if your application is particularly latency sensitive. For instance the small-packet round-trip time (i.e. a standard ping request) between my home machines (online via a good ADSL ISP) and the server I have state-side (as it tends to be cheaper there) is usually around 100ms (sometimes it sits at something approaching 120 for a time). For the vast majority of web-based services this level of latency is not going to be an issue at all.

share|improve this answer

I wouldn't give it much weight... US/UK isn't a huge hop. Even trans-pacific isn't a deal-breaker, as long as the endpoint network your on isn't congested. A solid network provider is far more important than exactly where you're located, in terms of providing a good experience to the users of the site.

share|improve this answer
Thanks for answering. Do you have any references I can check out? – T.J. Crowder Oct 5 '09 at 12:40
Like what... a physics textbook? – womble Oct 5 '09 at 23:27
@womble: The physics is the least of it. Switching equipment, capacity of the lines, etc., etc. have so far dominated. No, I meant do you have any reference for (say) statistics related to trans-atlantic hops to back up your saying it isn't a "huge hop." – T.J. Crowder Oct 6 '09 at 7:01
Well, ping from some strategic looking glasses would give you the answer the question "what is the latency across the Atlantic". I don't have a grand authoritative reference for why it isn't a problem, but I used to work for a big US-based hosting company who were looking at a European presence, but in the end their customer base was happy targetting Europe from an east coast US data centre, so the converse would be true. – womble Oct 6 '09 at 7:47

Are they complaining it's slow? What's your out-bound speed?

You might consider setting up a squid proxy/cache server in the US, or replicating your site to a server in the US, if it's really a major issue.

But I wouldn't [personally] expect it to matter that much.

share|improve this answer
Thanks. I should have been more clear, right now it's hosted in the U.S. but I'm looking to change providers, and surprisingly, there are now a lot of competitive UK providers (whereas just a few years ago data transfer costs were usually way too high here). – T.J. Crowder Oct 5 '09 at 11:44
then flip my countries around :) – warren Oct 5 '09 at 14:40

As other have mentioned the latency issue could be a factor. We have had issues with a CRM and SharePoint on links with latency of less than 100Ms due to the fact that the applications are very "chatty" and make many trips when opening pages. Most sites we fairly local to us in North America. WAN accelerators at the sites stoppe dthe calls and performance is good now and we did not have to obtain faster connections from the providers.

share|improve this answer

Latency is an issue. Pageloads will feel sluggish on the fastest connections. Make sure you've got good connectivity in the USA and good pings across the US. It helps if you are located in Chicago, New York, or California data centers. Chicago or New York being preferable if your customers are NOT in Asia. Run traceroutes. That really helps in choosing a webhost. Traceroute to (a european host) and

Choose an ISP in London UK if you need fastest connection in the States.

share|improve this answer
You do realise the question was asked 2.5 years ago ? – Iain Mar 24 '12 at 13:09
@Iain I still don't realize that posting an answer to an old question makes it appear on the TOP of questions. Should ask on meta about changing that behavior. – unixman83 Mar 24 '12 at 13:13
The behaviour has been discussed before. It won't be changing soon. The reason is, it allows new content/changes to be vetted by the community. – Iain Mar 24 '12 at 13:15

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.