SUMMARY: Performance checking and need for speed

Some time ago, I asked about ways to check site performance. A VP 
here had reported some speed concerns with the site. My monitoring 
tools showed no problems, yet I had a nagging feeling about it since 
it had a slow feel from time to time. (The original question is 
pasted in at the end of this message).

I received 40-some messages (!!), including many who went to my site 
or did traceroutes and reported, in some detail, on what they found! 
This was way more than I expected and I am deeply, deeply grateful.

The answer to my problem was somewhat surprising and nothing that 
anyone here could have guessed, given the data I provided (although a 
few people came close anyway). But along the way, I learned a great 
deal and am summarizing the whole thing for the benefit of all 
(especially me, since I will likely need to refer to this sometime).

The real answer? My site, located at Exodus, is connected through a 
Cisco switch. It connects to a larger switch at Exodus's end. The 
connection between the two is supposed to automatically arbitrate 
protocols but something screwed up and my switch was talking 
half-duplex while the Exodus switch was talking full-duplex. Or 
something like that. We were seeing a lot of spurious errors. Because 
those self-correct, the data was flowing, but somewhat slowly due to 
the retransmissions. When we manually configured the switches to use 
the same protocol, speed noticeably improved and responsiveness is 
remarkably better. It has the snappy feeling that was missing.

What else did I learn?

- I had noted that no customers had ever complained about speed. 
Reason is that with anything other than a fast connection, there was 
no visible effect; and besides, speed was never bad -- just not 
snappy. Important lesson: Everyone knows customer complaints mean 
something; but receiving no complaints should not lull you into 
complacency.

- Several ran monitors which also reported decent speed. Lesson: 
Monitors mean something but may not reveal subtle performance 
problems. Don't disregard subjective reports or the feeling that 
something ain't right. Especially from VPs!

- Quite a few people looked at the HTML of my home page and made some 
good suggestions (not yet implemented). Most important is to design 
out, if I can, the nested tables. I was not aware of how they impact 
performance. The data comes across the line but then the browser has 
to build the page. Nested tables are hard work.

- Large tables are also worth a look. The table is displayed only 
after the whole thing has arrived so usually best to have smaller 
tables.

- Lose the Javascript. I agree. You should see all the Javascript 
that was here when I started. I just have a little left.

- Home page has too many keywords.

- And some redundant font tags.

- Learned a lot about the protocols and connection speeds. Basically, 
we have a 1 Mb/s connection that can burst 10 Mb/s. We were throttled 
by the errors but now see full speed transfers all the time.

- Some load check services and monitors:

   http://www.netmechanic.com/cobrands/zdnet/loadcheck/
   http://www.netmechanic.com/monitor.htm
   http://keynote.com
   http://www.decise.com
   http://Superstats.com

Finally: Thanks to all who contributed.

Moe Rubenzahl
moe(at)maxim-ic.com

Director of Internet Marketing
Maxim Integrated Products
120 San Gabriel Dr.
Sunnyvale, CA 94086

408-331-4149

- - -

Original question:

>  I need a good way to look at the performance of our web site. We have
>  a small home page (35K), yet some people (notably one of our VPs,
>  connecting from home, using AT&T @Home and a cable modem) report our
>  site does not load as quickly as it should. I can't say for sure
>  whether he is wrong or right and have no real performance monitors in
>  place. I do sometimes see a pause with one page or another.
>
>  My question is whether anyone can recommend some site performance
>  services or tools or other ideas.
>
>  A little background:
>
>  - Site is http://www.maxim-ic.com
>
>  - We are running four Unix servers, co-located at Exodus, and they
>  are very lightly loaded. We serve about 13,000 PDF data sheets
>  (typically 50K each) a day and around a million static pages a month.
>  Apache is on one machine; database and Cold Fusion on a second; the
>  other two are loafing.
>
>  - We run Apache for our static pages and some of the site -- maybe
>  20% of traffic -- comes from Cold Fusion, serving from Sybase SQL.
>  Perceived speed problems are not limited to Cold Fusion-served pages.
>
>  - We use server side include to serve our page headers and footers. I
>  know it's not the best practice but figured that with our processors
>  so lightly loaded, we were OK.

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