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A slightly off-topic question tinged with a touch of envy that you get to work on D. Many HN readers are apprehensive of the use of D because it is garbage col

by srean 9y ago

A slightly off-topic question tinged with a touch of envy that you get to work on D. Many HN readers are apprehensive of the use of D because it is garbage collected and conjecture that it is not appropriate for low latency and/or high throughput work loads. Correct me if I am wrong, but that is exactly the kind of load the sociomantic needs to address. I have thoroughly enjoyed the relevant Dconf videos but it would be great to hear some first hand account. BTW is the move to D2 done ?

nemanjaboric 9y ago
Oh, I'm aware this is a late reply, but it's better than nothing. Yes, what you describe is exactly the kind of load we're addressing, and we're not getting GC to be in the way, simply by making usage of the reusable memory buffers, which are allocated in the first few requests, and then always reuse/recycled & fetched from the pool, so that we're not giving a chance for GC to kick in (as explained in the great blog post series, in D, GC mark&sweep will kick in only on allocations, completely deterministic: https://dlang.org/blog/category/gc/ https://dlang.org/blog/category/gc/). Ocean provides some help here: https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src/ocean/core/Buffer.d https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src... https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src/ocean/util/container/pool/FreeList.d https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src..., etc. This makes D completely suitable for these kinds of applications, and from my experience, none of D's features or the misfeatures is making such implementations hard. D2 move is not yet completely done. We're still writing code that's compatible in both D1 and D2. For example, DHT node project (https://github.com/sociomantic-tsunami/dhtnode https://github.com/sociomantic-tsunami/dhtnode) and libraries on which it's depending on such as ocean (https://github.com/sociomantic-tsunami/ocean https://github.com/sociomantic-tsunami/ocean) and swarm (https://github.com/sociomantic-tsunami/swarm https://github.com/sociomantic-tsunami/swarm) are able to run in D2 with no performance penalties, but they still don't use D2-only constructs.
- srean 9y ago
  Appreciate your reply and welcome to HN.
  - nemanjaboric 9y ago
    Thanks!

by srean 9y ago

nemanjaboric 9y ago

Oh, I'm aware this is a late reply, but it's better than nothing. Yes, what you describe is exactly the kind of load we're addressing, and we're not getting GC to be in the way, simply by making usage of the reusable memory buffers, which are allocated in the first few requests, and then always reuse/recycled & fetched from the pool, so that we're not giving a chance for GC to kick in (as explained in the great blog post series, in D, GC mark&sweep will kick in only on allocations, completely deterministic: https://dlang.org/blog/category/gc/ https://dlang.org/blog/category/gc/). Ocean provides some help here: https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src/ocean/core/Buffer.d https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src... https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src/ocean/util/container/pool/FreeList.d https://github.com/sociomantic-tsunami/ocean/blob/v2.x.x/src..., etc. This makes D completely suitable for these kinds of applications, and from my experience, none of D's features or the misfeatures is making such implementations hard. D2 move is not yet completely done. We're still writing code that's compatible in both D1 and D2. For example, DHT node project (https://github.com/sociomantic-tsunami/dhtnode https://github.com/sociomantic-tsunami/dhtnode) and libraries on which it's depending on such as ocean (https://github.com/sociomantic-tsunami/ocean https://github.com/sociomantic-tsunami/ocean) and swarm (https://github.com/sociomantic-tsunami/swarm https://github.com/sociomantic-tsunami/swarm) are able to run in D2 with no performance penalties, but they still don't use D2-only constructs.

srean 9y ago
Appreciate your reply and welcome to HN.
- nemanjaboric 9y ago
  Thanks!