Is there a way to reuse rules between queries in different transaction functions?

@stijn only way I can think of is to write a transaction function that returns the rules, then use datomic.api/invoke to retrieve them in other transaction functions

there are probably not a lot of nixos users using datomic, but at the moment all these commands using /bin/bash would fail on nixos

ag /bin/bash
bin/console
1:#!/bin/bash

bin/repl-jline
1:#!/bin/bash

bin/transactor
1:#!/bin/bash

the fix is rather trivial, just /bin/bash -> /usr/bin/env bash, and it's generally better to use that form anyway

andrea.crotti: just replace them with /usr/bin/env bash

yeah I know that's the fix

I was suggesting that they could fix it datomic

whoops I thought this was the NixOS channel actually x) My bad!

I can probably report it somewhere

(I'm using Slack via the IRC gateway)

Hey All, I'm deploying my little datomic project to aws instances, but the default c3.large is too expensive. I've been trying to use some of the smaller instances, but with no luck yet. Some of the possibilities like t2.small don't seem to be supported. If I try to run bin/datomic ensure-cf on properties file with that instance indicated, I get an error Key not found: t2.small. Does anyone know of a workable deploy with a cheaper instance?

m3.medium @ezmiller ?

I'll give that a shot @marshall. Was hoping to try something a bit smaller, to save more money...

Is there a list somewhere of which instances are available, and what specifically an instance needs to support in order to run a datomic transactor?

@ezmiller77 If you look at the generated cf template JSON you’ll see a map of all instance types; theoretically you can use any of them - some folks have been able to get the transactor running on small/micro instances, but you’d need to heavily tweak heap and memory index settings

if you have any substantial load, I would avoid burst instances

I really don't have any substantial load at this point. Any links to guidance on tweaking heap and memory index settings would be much appreciated. Thanks!

depends how much memory you’re working with; the JVM can (and will) require more than you specify with Xmx, plus you need some for your OS

the memory-index-max will be taken from the heap

so you need to reduce object-cache-max to allow that

and/or reduce memory-index-max

default is for object cache to take half of allocated heap

Thx!

@ezmiller77 https://stackoverflow.com/questions/45501981/is-there-any-way-to-use-t2-small-ec2-instance-when-deploying-datomic-transactor FYI

for what it’s worth - claim to use a t2.small

Oh yeah, I tried that (some of my commments below the answer there...) Wasn't able to get that to work in the end...

Might try again when I have a moment.

definitely need to adjust heap, probably object cache, maybe mem index max

@ezmiller77 we're using t2.small transactors. When calling ensure-cf we use any key that's valid/found. Then we manually enter "t2.small":{"Arch":"64h"}, into the produced cf.json. My java options are: java-xmx=1500m and I don't remember having to change the object cache or mem index max

@petterik : that sounds much like what the stackoverflow question that @marshall linked says. Maybe I need to give it another shot!

@petterik @ezmiller77 http://docs.datomic.com/changes.html#0.9.5561.50 As of 0.9.5561.50 the ensure-cf script should work fine with t2.small (and pretty much all the other instance types)

let me know if that’s not true, b/c it should be 🙂

@marshall : good to know. If we are on a free version, we aren't able to upgrade is that right?

I'm on an earlier version...

depends when your Starter license maintenance period expires

0.9.5544

you can access updated versions until your maint. period ends (a year)

@ezmiller77 Looks like you got Starter in Jan 2017, so your license key is valid for all versions up until Jan 2018

then after that you are frozen at whatever version you are on?

until you upgrade to a paid license

@marshall I'm on 0.9.5561, but I'll let you know if specifying t2.small doesn't work when I upgrade 🙂