Viewing profile — mjb

Among the thugs, Heat, and Dirt are all great reads. Heat is my favorite of them. Highly recommended if you've ever worked in a kitchen, or considered it.

You absolutely can run agents on a regular VM. But if you want to build multi-tenant and multi-agent systems with strong security boundaries, then having a VM or MicroVM per agent …

AWS AgentCore runtime has been around for about a year: https://docs.aws.amazon.com/bedrock-agentcore/latest/devguid... (spoiler, it's the same underlying technology as the Lambda …

A dead comment says: > Of course, this assumes independent events. World Cup, super bowls, etc break these assumptions. Yes, this is very true. The model here works for Poisson arr…

One explanation would be that more load could mean higher (absolute) variance in queue length, and therefore higher latency especially at higher percentiles. It doesn't work out th…

> What's conspicuously missing is the plot of performance when you do have a well tuned queue in front of the service. As in between the service and the load balancer? There's alre…

> With serializable, you need to be a little careful not to have hot rows. Avoid them by sharding commonly written values Unfortunately, serializable isolation requires detecting o…

The 70s, if you want to be pedantic (e.g. Gifford's "Weighted Voting for Replicated Data" or Thomas's "A Majority Consensus Approach to Concurrency Control for Multiple Copy Databa…

This is cool, and a really fun reminder that "majority" isn't required for quorum systems (it just happens to be the simplest way of thinking about it, and optimal in some senses).…

Good read. I've always been a little confused about this framing of WSI. The observation that detecting read-write conflicts is sufficient for serializability dates back to at leas…

Cool article! > This is why free -h on a Linux box can look alarming. You see almost no “free” memory, but most of it is “available” - and the page cache is using it. And other buf…

Indeed. Collecting cameras, and talking about cameras, is a very different hobby from photography. That's OK! Both can be fun. Inspired me to write this blog post: https://brooker.…

The haters will hate, but tap guides are great (e.g. https://biggatortools.com/v-tapguide-faqs , but even a block of hard wood with a clearance hole drilled in it works fine). Unle…

I don't think either is a bad choice, but Aurora has some advantages if you're not a DB expert. Starting with Aurora Serverless: - Aurora storage scales with your needs, meaning th…

I spoke about this exact thing at a conference (HPTS’19) a while back. This can work, but introduces modal behaviors into systems that make reasoning about availability very diffic…

When does AP help? It helps in the case where clients are (a) able to contact a minority partition, and (b) can tolerate eventual consistency, and (c) can’t contact the majority pa…

Practically, the difference in availability for typical internet connected application is very small. Partitions do happen, but in most cases its possible to route user traffic aro…

Yes, you can do stuff like that. You might enjoy the CRAQ paper by Terrace et al, which does something similar to what you are saying (in a very different setting, chain replicatio…

(Op here) No deadlocks needed! There’s nothing about providing strong consistency (or even strong isolation) that requires deadlocks to be a thing. DSQL, for example, doesn’t have …

(OP here). The point of that section, which maybe isn’t obvious enough, is to reflect on how eventually-consistent read replicas limit the options of the database system builder (r…

(OP here). I don’t love leaking this kind of thing through the API. I think that, for most client/server shaped systems at least, we can offer guarantees like linearizability to al…

That’s a fair point. To be fair to the academic definitions, “eventually consistent” is a quiescent state in most definitions, and there are more specific ones (like “bounded stale…

Read-your-writes is a client guarantee, that requires stickiness (i.e. a definition of “your”) to be meaningful. It’s not a level of consistency I love, because it raises all kinds…

The point is that, in a disaggregated system, the transaction processor has less flexibility about how to route parts of the same transaction (that section is a point about interna…