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DNS lookup on Repeat View: why? - Printable Version

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DNS lookup on Repeat View: why? - aaronpeters - 11-18-2010 10:19 PM

hi Pat,

Repeat View tests show DNS lookups for all hosts, just as for First View tests. Wouldn't it be better (=more realistic) to *not* clear DNS cache before doing the RV test?

I always interpret RV as "the user visits the same page 1 day after the First View".
If there is more time between FV and RV, most likely the page objects will not be in browser cache anymore, so the whole RV test results are useless.

Do you agree on my "1 day later" point of view?
If so, wouldn't it make sense to *not* clear the DNS cache?


RE: DNS lookup on Repeat View: why? - pmeenan - 11-18-2010 10:53 PM

Depends on the TTL of the DNS records. I'm used to seeing really short TTL's (like 1 minute - 1 hour) but if it is common for TTL's to be > 24 hours it might be worth looking at.


RE: DNS lookup on Repeat View: why? - aaronpeters - 11-18-2010 10:56 PM

If the TTLs for most hosts are that short, then it makes perfect sense.
Txs.