djspiewak

Understanding Comparative Benchmarks

I'm going to do something that I don't normally do, which is to say I'm going to talk about comparative benchmarks. In general, I try to confine performance discussion to absolute metrics as much as possible, or comparisons to other well-defined neutral reference points. This is precisely why Cats Effect's readme mentions a comparison to a fixed thread pool, rather doing comparisons with other asynchronous runtimes like Akka or ZIO. Comparisons in general devolve very quickly into emotional marketing.

But, just once, today we're going to talk about the emotional marketing. In particular, we're going to look at Cats Effect 3 and ZIO 2. Now, for context, as of this writing ZIO 2 has released their first milestone; they have not released a final 2.0 version. This implies straight off the bat that we're comparing apples to oranges a bit, since Cats Effect 3 has been out and in production for months. However, there has been a post going around which cites various compar

edwardGunawan

object WriteToFile {
  def create[F[_]](
    queue: Queue[F, Option[Either[Throwable, String]]],
    destinationFile: String
  )(implicit blocker: Blocker,
    F: Concurrent[F],
    cs: ContextShift[F]): F[WriteToFile[F]] = {

    def toFile(fileName: String): Pipe[F, String, Unit] =
      _.through(text.utf8Encode)

edwardGunawan

def toFile(fileName:Sting, upstream:Stream[IO,String])(implicit blocker: Blocker):Stream[IO, Unit] = 
  upstream.through(text.utf8Encode).through(io.file.writeAll(Paths.get(fileName), blocker))

Daenyth

Parallels between map and similar functions

map          :: F[A] => (A =>     B)   => F[B]
flatMap      :: F[A] => (A =>   F[B])  => F[B]
traverse     :: G[A] => (A =>   F[B])  => F[G[B]]
flatTraverse :: G[A] => (A => F[G[B]]) => F[G[B]]
traverse_    :: F[A] => (A =>   F[B])  => F[Unit]

bmaupin

See also:

• Free backend hosting
• https://free-for.dev/#/?id=dbaas

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Amazon DynamoDB	⚠️ Proprietary NoSQL	25 GB	⚠️ Payment method required
Amazon RDS	⚠️ Proprietary RDBMS		⚠️ Only free for 1 year
Azure SQL Database	MS SQL Server		⚠️ Only free for 1 year
👉 Clever Cloud	PostgreSQL, MySQL, MongoDB, Redis	256 MB (PostgreSQL)	Max 5 connections (PostgreSQL)

ivelin

pragma solidity ^0.4.17;
contract Auction {
    
    // Data
    //Structure to hold details of the item
    struct Item {
        uint itemId; // id of the item
        uint[] itemTokens;  //tokens bid in favor of the item
       
    }

xen

from web3 import Web3, HTTPProvider, IPCProvider

web3 = Web3(IPCProvider('/Users/xen/Library/Ethereum/rinkeby/geth.ipc'))
# web3 = Web3(IPCProvider('/Users/xen/Library/Ethereum/geth.ipc'))

print(web3.eth.blockNumber)
print(web3.eth.accounts)

djspiewak

Thread Pools

Thread pools on the JVM should usually be divided into the following three categories:

1. CPU-bound
2. Blocking IO
3. Non-blocking IO polling

Each of these categories has a different optimal configuration and usage pattern.

robertpainsi

Commit Message Guidelines

Short (72 chars or less) summary

More detailed explanatory text. Wrap it to 72 characters. The blank
line separating the summary from the body is critical (unless you omit
the body entirely).

Write your commit message in the imperative: "Fix bug" and not "Fixed
bug" or "Fixes bug." This convention matches up with commit messages

andredumas

Bollinger Bands calculation and rendering demo.