Mailing List Archive

FW: Queries and the "lag" problem
As we discussed over the phone, my SELECT query should have had a LIMIT 99 clause on it.

I will put a LIMIT clause on all future queries, for safety's sake.

I don't want the shame of causing a 52-minute lag again!

Ed Poor

-----Original Message-----
From: Poor, Edmund W.
Sent: Friday, November 22, 2002 8:19 PM
To: 'Brion VIBBER'
Subject: Queries and the "lag" problem


Brion,

A few minutes ago, I submitted a SELECT query.

But, thinking it might be too long (since I had neglected to put "limit 99" on it) I tried to abort the query by hitting the Stop button on my browser.

Well, since then, wikipedia has been completely unresponsive. Which leads me to 2 thoughts:

* Bad Ed! Don't submit unbounded queries like that (I should be more careful)

but perhaps more generally,

* Could the slowness of the server feed on itself? If users hit stop or just close their page, does the server wait and wait for a long time trying to give them the page they just said they no longer want? And then does this long wait make others give up and leave, which only makes the server wait for them too?

Or maybe it's just a coincidence. I'd love to know what the logs show in this case tonight. It happened some time between 8:00 P.M. and 8:15 P.M., US East Coast time.

Ed Poor