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apoorvgarg

apoorvgarg on Hacker News

Re:Joe Armstrong has died on Saturday April 20, 2019 @10:35AM (#19706709)
https://www.youtube.com/watch?v=37wFVVVZlVU

This recent panel (Armstrong, Hewitt and Hoare) discussion on concurrency was the first time I got to know about him and it gave me a lot of food for thought.

Re:You Are Not Google (2017) on Thursday April 04, 2019 @05:54PM (#19577485)
Before we make a technology choice, we should be clear what those choices are. SQL is a query language and DynamoDB is a database. "NoSQL" technologies can be fronted with SQL interfaces. Relational databases can vary a lot too in their ACID compliance ("I" being the component with maximum variance).

The choice of technology should first be based on the problem and not whether it is serverless. Choosing DynamoDB when your application demands strict serializability would be totally wrong. I hope more people think about the semantic specifications of their applications (especially under concurrency).

Re:Practical Go: Real-world advice for writing maintainable Go programs on Thursday February 21, 2019 @11:36PM (#19223163)
What would be the signature of your gcd function ?
Re:Practical Go: Real-world advice for writing maintainable Go programs on Thursday February 21, 2019 @04:54PM (#19220901)
Yes, and I think the quoted paragraph has so much more to do with coding around interfaces (behaviour) than with abstraction using non-exported package symbols.
Re:Practical Go: Real-world advice for writing maintainable Go programs on Thursday February 21, 2019 @04:23PM (#19220703)
Regarding single-letter variables, mathematical functions might be an exception. I think writing func gcd(a, b int) int {...} is better than other alternatives. There is simply no need to assign any more meaning to the arguments other than their type.
Re:Ask HN: Do you wish AWS Cloudwatch was smarter? on Friday January 11, 2019 @11:34AM (#18884628)
To make your comment useful [0], I would suggest explaining why and giving some context. For example, you could start with the size of your AWS infra, which other tools are you using other than CloudWatch etc.

[0] https://news.ycombinator.com/newsguidelines.html

Ask HN: Do you wish AWS Cloudwatch was smarter?

Posted by apoorvgarg on Friday January 11, 2019 @03:51AM
from the ask-hn dept.

I am building a simple integration with AWS cloudwatch that basically scrapes metrics from cloudwatch and does the following:1. learns what is normal from past behaviour and alerts on abnormalities. Thus no need to set and maintain alert conditions on hundreds of metrics (at least not on the low level non-SLA metrics).2. auto clusters the above into incidents. Example - if 100 EBS volumes have...

( Read More... | 3 comments | on HN )
Re:Ask HN: If HN had a follow feature, who would you follow? on Sunday November 18, 2018 @05:19AM (#18479668)
The question is not suggesting a follow feature. It is just a hypothetical. The aim is to list great contributors on this platform, so that anyone looking at this thread can learn something new from their contributions.
Re:Amazon Itself Runs on Oracle DB: Larry Ellison [video] on Sunday November 18, 2018 @01:18AM (#18479117)
"Oracle DB is at least 10 years ahead of anything else"

Is this just sales talk or does it hold any technical truth?

Ask HN: How fast is an AWS auto scaling group?

Posted by apoorvgarg on Wednesday October 17, 2018 @10:22AM
from the ask-hn dept.

I have been struggling to find an answer to this simple question. What is the rate at which new instances can be created in an autoscaling group?Let's say if there is a sudden spike in traffic, and I need to go from 50 EC2 instances to 300. How long would it take (lets assume a pre-baked AMI). If every EC2 takes x minutes to start up, in how much time will my auto scaling group achieve the...

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Re:Evergreen: a React UI Framework built by Segment on Wednesday October 17, 2018 @05:13AM (#18237412)
This might be useful https://github.com/ant-design/ant-design-pro
Re:Why you can have millions of goroutines but only thousands of Java ... on Tuesday October 09, 2018 @01:46AM (#18173599)
Paging has nothing to do with this. When I say 1 MB thread stacks, it means the maximum size of that thread's stack in the virtual address space [0]. Each of these million threads could be using only a few KBs for its stack (out of that 1 MB of stack space). That would imply a few gigs of physical memory => no paging.

[0] http://man7.org/linux/man-pages/man3/pthread_attr_setstacksi...

Re:Why you can have millions of goroutines but only thousands of Java ... on Tuesday October 09, 2018 @01:27AM (#18173541)
Nobody is suggesting that you create a million threads. But to think that it is not possible without TBs of physical memory is a fallacy (for 64-bit machines).

The thread switching costs itself could be prohibitive to performance. IIRC, goroutine switching cost is roughly 1/10th of linux thread switching costs.

Re:Why you can have millions of goroutines but only thousands of Java ... on Monday October 08, 2018 @09:37PM (#18172733)
Again, all this confusion is due to not being clear about virtual and physical memory. Every OS thread in linux does have a fixed virtual memory size (it is claimed when a thread is created, but this claim is on the virtual memory. This value is fixed at creation time). As you grow your program's conceptual stack in this virtual memory area, you would soon hit new pages of virtual memory, leading to page faults and linux allocating physical memory for you.

From a virtual memory standpoint, every thread would appear to have a fixed size which can be set when you create it. [0]

From a physical memory standpoint, every thread would appear to have a dynamic size (but bounded by the virtual memory size of course).

[0] http://man7.org/linux/man-pages/man3/pthread_create.3.html

Re:Why you can have millions of goroutines but only thousands of Java ... on Monday October 08, 2018 @06:35PM (#18171912)
I think it is so important to not arbitrarily throw words like 'RAM' in such discussions, and use more unambiguous terminology such as - virtual address space and the resident set size (RSS).

On a 64-bit machine, with 1MB stack size (this is a claim on the virtual address space, not the physical memory), you can have millions of threads too (that you may hit a lower limit due to other OS level knobs is another matter).

Re:Google’s revamped Cloud Source Repositories in beta on Thursday September 20, 2018 @10:31AM (#18032676)
how many gcp products has google abandoned in total?
Re:The magic of asyncio explained on Wednesday August 08, 2018 @02:47AM (#17713697)
Thanks for the perspective (especially for me, since Go is my primary language.)

Just to clarify, the primary target audience for the article is anyone who is getting started with asyncio (although I know of people who have been using asyncio, but don't really understand whats going on).

Re:APM powered by open source on Thursday June 21, 2018 @10:00AM (#17365139)
Here's the link to try it out - apm.archsaber.com

APM powered by open source

Posted by apoorvgarg on Thursday June 21, 2018 @09:56AM
from the self-post dept.

I built an APM solution powered by open source projects (think Jaeger, Apache Flink etc) and doesn't burn a hole in your pocket. Would love to get feedback.You can read more about it @ https://www.reddit.com/r/devops/comments/8sjpas/apm_powered_by_open_source/

( Read More... | 1 comment | on HN )