ChainLoad

chainload is a GoChain/Ethereum blockchain load generator.

How to use

By default, simply executing chainload will fire 1 transaction per second at http://localhost:8545 with chain id 1234. Reports are logged every 30s, with pprof and other metrics available via expvar.

The target url(s), transaction rate, chain id, and more can be set via flags:

chainload --help

Usage of chainload:
  -amount uint
    	tx amount (approximate) (default 10)
  -cycle duration
    	how often to cycle a sender's account (default 5m0s)
  -dur duration
    	duration to run - omit for unlimited
  -gas uint
    	gas (approximate) (default 200000)
  -id uint
    	id (default 1234)
  -pass string
    	passphrase to unlock accounts (default "#go@chain42")
  -pprof string
    	pprof addr (default ":6060")
  -senders int
    	total number of concurrent senders/accounts - defaults to tps
  -tps int
    	transactions per second (default 1)
  -urls string
    	csv of urls (default "http://localhost:8545")

Examples:

chainload -id 9876 -urls http://node1:8545,http://node2:8545 -tps 100 -senders 50 -dur 5m

chainload version
> chainload version: 0.0.18

How it works

Accounts are managed locally under keystore/. Pre-existing accounts are reused and new ones are created as necessary. One seeder goroutine is started per url to seed funds to senders, and to continually re-claim funds from other accounts. Senders goroutines continually send txs to a set of receivers, while periodically cycling out the sender and receiver addresses. The gas and amount of each transaction varies randomly from the suggested approximate values.

Problems

At high volume, the error Too many open files may occur. This system limit can be inspected via ulimit -n, and temporarily raised via ulimit -n <new limit>. It can be permanently set in /etc/security/limits.conf by adding a line like:

root             soft    nofile          100000

Releases

CI releases are manually triggered. If no tag is set, then the commit hash will be used as the version and docker tag. To produce a versioned release, first tag the desired commit (e.g. v0.1.0), then approve the CI release step (or re-run, if a commit hash release has already been produced).