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Java at Alibaba [pdf]

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Re: Java at Alibaba [pdf]

#4
Impressive stuff. They have basically forked their entire backend stack, starting from the OS and moving upwards. I am particularly interested in how much AliOS deviates from mainline Linux.

Re: Java at Alibaba [pdf]

#6
Cool presentation! I'm not sure why the submitter editorialized this title, instead of the straightforward "Java at Alibaba" title from the presentation.

Re: Java at Alibaba [pdf]

#7
post #4

Impressive stuff. They have basically forked their entire backend stack, starting from the OS and moving upwards. I am particularly interested in how much AliOS deviates from mainline Linux.

>Alibaba Runs Millions of Custom JVMs

>They have basically forked their entire backend stack, starting from the OS and moving upwards.

I doubt this being a cool thing. Sure, they are the second biggest IT employer in the country, and have excess resources for everything, but...

A thing about big dotcoms - architects there try to use off-the-shelf software for everything, even if the software is clearly unsuited for the task and its use will require hacks and massive re-engineering.

Putting efforts to use of off-the-shelf software without modifications and hacks greatly reduces all aspects of infrastructure support burden.

BUT, attempting to use of off-the-shelf software everywhere at all costs, that will of course give you problems. And the bigger your are, the worse this is. Read the article from a month ago how Alibaba got stuck with using MySQL for mission critical tasks, and how much efforts they put to "unhack" it

Re: Java at Alibaba [pdf]

#8
Either I'm being very dense, or something doesn't quite make sense about these numbers.

The slides say that on the busiest day of the year, they were serving around 175,000 transactions per second (126k of which, or maybe additionally, were payments).

On the next slide it says they have 'millions of JVMs' running an 'insurmountable number' of requests.

Is each JVM really taking 10s+ per transaction? Even assuming those JVMs are split between servers, messaging, caching, database, etc, I don't get why they need millions of them to handle c. 200k transactions per second.

Needless to say, I am not DevOps, so feel free to set me right.

Re: Java at Alibaba [pdf]

#9
post #4

Impressive stuff. They have basically forked their entire backend stack, starting from the OS and moving upwards. I am particularly interested in how much AliOS deviates from mainline Linux.

> They have basically forked their entire backend stack, starting from the OS and moving upwards.

Isn't this pretty common at the $XXX billion dollar tech companies like Google, Facebook, etc?

Re: Java at Alibaba [pdf]

#10
post #8

Either I'm being very dense, or something doesn't quite make sense about these numbers. The slides say that on the busiest day of the year, they were serving around 175,000 transactions per second (126k of which, or maybe additionally, were payments). On the next slide it says they have 'millions of JVMs' running an 'insurmountable number' of requests. Is each JVM really taking 10s+ per transaction? Even assuming tho…

Probably for non-transactional stuff I'm guessing. For every transaction there are probably 100 reads from various sources. Not to mention all the other stuff, from invoicing to reporting.
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