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Towards Optimal Transaction Scheduling
Originally from muratbuffalo.blogspot.com/feeds/posts/default
August 13, 2025 • Roasted by Patricia "Penny Pincher" Goldman Read Original Article

Ah, yes, another “stellar systems work.” I always get a little thrill when the engineering department forwards me these academic love letters. It’s truly heartwarming to see such passion for exploring the “schedule-space.” It reminds me of my nephew’s LEGO collection—intricate, impressive in its own way, but ultimately not something I’m going to use to build our next corporate headquarters. The author thinks it makes a “convincing case.” That’s nice. Convincing whom? A tenure committee?

Because as the person who signs the checks—the person whose job is to prevent this company’s money from being shoveled into a furnace labeled "INNOVATION"—my “schedule-space” involves calendars, budgets, and P&L statements. And when I see a claim of “up to 3.9x higher throughput,” I don’t see a solution. I see a price tag with a lot of invisible ink.

Let’s do some real-world math, shall we? Not this cute little “toy example” with four transactions where they got a 25% improvement. Oh, wow, a 25% improvement on a workload that probably costs $0.0001 to run. Stop the presses. Let’s talk about implementing this… thing… this R-SMF, in our actual, revenue-generating system.

First, they propose a “simple and efficient” classifier to predict hot-keys. Simple. I love that word. It’s what engineers say right before they request a multi-year, seven-figure budget. This “simple” model needs to be built, deployed, and, as the paper casually mentions, “periodically retrained to adapt to workload drift.”

Let’s sketch out that invoice on the back of this research paper:

So, before we’ve even processed a single transaction, we’re at $750,000 in the first year just to get this “promising direction” off the ground.

And for what? For a system whose performance hinges entirely on the accuracy of its predictions. The paper itself admits it:

with poor hints (50% wrong), performance can drop.

A 50% chance of making things worse? I can get those odds in Vegas, and at least the drinks are free. They say the system can just “fall back to FIFO.” That’s not a feature; that’s a built-in excuse for when this whole Rube Goldberg machine fails. We just spent three-quarters of a million dollars on a fallback plan that is literally what we are doing right now for free.

Now, about that glorious 3.9x throughput. That’s an “up to” number, achieved in a lab, on a benchmark, with “skewed workloads.” Our workload isn’t always perfectly skewed. Sometimes it’s just… work. What’s the performance on a slightly-lumpy-but-mostly-normal Tuesday afternoon? A 1.2x gain? A 5% drop because the classifier got confused by a marketing promotion? The ROI calculation on “up to” is functionally infinite or infinitely negative. It's a marketing gimmick, not a financial projection.

Let’s say we get a miraculous, sustained 2x boost in transaction throughput. Fantastic. We’re processing twice the orders. Our current transaction processing cost is, let's say, $1 million a year. A 2x improvement doesn't cut that cost in half. It just means we can handle more load on the same hardware. So, the "value" is in deferred hardware upgrades. Maybe we save $250,000 a year on servers we don't have to buy yet.

So, we spend $750,000 in year one, with ongoing costs of $250,000+ a year, to save $250,000 a year. The payback period is… let me see… never. The company goes bankrupt first.

And the grand finale? The author’s brilliant idea to solve the system's inherent flaws:

a natural extension would be to combine the two: use R-SMF's SMF+MVSchedO… [and] apply Morty-style selective re-execution

Oh, absolutely! Let’s take one experimental system that relies on a psychic machine-learning model and bolt on another experimental system that speculatively executes and repairs itself. What could possibly go wrong? We’re not running a database; we’re running a science fair project with the company’s future as the tri-fold poster board.

Look, it’s a very clever paper. Truly. It’s an adorable exploration of theoretical optimization. The authors should be very proud. They’ve made a convincing case that you can spend a colossal amount of money, introduce terrifying new layers of complexity and failure modes, and hire an army of consultants for a chance at improving performance under laboratory conditions.

It's a wonderful piece of work. Now please, file it under “Academic Curiosities” and let the adults get back to running a business.