Friday, February 27, 2009

Conversation with a Web Thread

DD: Hi Mr. Web Thread and thanks for joining us.
WT: My pleasure. Do you mind if I stay in the pool?

DD: Hmm? Sure, why not. So, can you please tell us how is your life nowadays?
WT: Life has been pretty good. I have become very popular recently and came to perform some massive gigs in highly trafficked web sites. I really like this pool.

DD: Mmhh, okay. How do you think developers treat you, nowadays?
WT: Well, I am glad you ask. I think things have improved a lot, thanks to the emergence of concepts like continuations and AJAX. Still, I sometimes get badly beaten by some reckless coders. This pool is awesome.

DD: So, if you were to give a piece of advice to these programmers, what would it be?
WT: I think that these developers only need to understand what is the ultimate goal of my life.

DD: Which is?
WT: Coming back to that pool!

DD: Pardon me?
WT: You see, I get pulled of this pool very often and sometimes I am forced out of it for too long. In that case, I am like a fish out of water. And when I suffer like that, the whole application suffers.

DD: So what you are saying is that developers should thrive to let you return to the pool as quick as possible?
WT: Absolutely.

DD: Whatever the cost may be?
WT: Well, it depends of course, but if they can afford letting me return with slightly stale data, that is the thing to do.

DD: Where would they get such a stale data from?
WT: Oh, I realize I never introduced you to Mrs. Web Thread, née Cache. She usually takes care of this.

DD: But ladies, sorry, caches are complex. They require eviction strategies, invalidation messages broadcasts, etc.
WT: Or not. You can use a simple time-evicted opportunistic cache, provided it matches your business needs.

DD: Ah, I see, something like a 5 minutes cache.
WT: Or 5 seconds.

DD: You got to be kidding me, what's a 5 seconds cache worth?
WT: Do you have any idea of all the things I can do in 5 seconds? Do you realize that it is an agonizing eternity for me?

DD: Well, uh, I guess not. Let us lighten up the debate a little. Now that you are a rock star, thanks to your success in multi-million users web sites, do you get to sign a lot of autographs? Do people recognize you a lot?
WT: Sure, I can hardly go anywhere without being spotted. But, believe it or not, it still happens that I get mixed up with my cousins.

DD: Oh, you have cousins?
WT: Yes, Worker Thread and Background Thread. Sometimes, I get confused with one of them and receive way too much work to do or work that simply does not concern me at all.

DD: What do you do in that case?
WT: As I said before: I become grumpy and the whole web tier suffers with me too. I kind of like to share my pain!

DD: OK, Mr. Web Thread, I think it is time we wrap up now. Thanks a lot for your time and sharing your experience with us.
WT: You are welcome. Now back to the pool.

Splash!