Skip to content

My benchmark numbers seem fake. What did I break?

VPS Hosting by sarahjey 16 replies 1.3K views
8 #1

Hi everyone!! Sorry if this is a dumb question. I ran YABS on my new €4 VPS from Hetzner and the disk results are insane?? 12GB/s sequential read?? That is faster than my laptop's SSD!!

Here is the paste:
fio test: read=12100MB/s, write=11800MB/s, IOPS=2.1M
CPU: 3194 MHz reported but feels slower in real use

Is this normal?? Did I configure something wrong?? I ran it three times and got similar results. My friend says tmpfs but I do not know what that means. Thank you!!

learning on $5 VPS and prayers
4 #2

My $3 VPS at RackNerd gets 14GB/s read lol

Your CPU freq is fake too, check scaling governor, probably powersave or ondemand

Real perf:
Echo performance | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

Then rerun and cry gg

world record: 4min Arch install
9 #3

Lol yeah this is classic tmpfs /tmp behavior

Ngl I fell for this once benchmarking an inference setup, thought I had NVMe-tier local scratch for model weights. Was actually RAMdisk. The IOPS number should have been a clue—2.1M on a $4 box is physically impossible without something weird going on.

Check your mount points: df -h | grep tmpfs

Real NVMe on these budget tiers is more like 200-800MB/s seq. Still fine for LLM serving if your working set fits in RAM.

For actual training workloads you need VRAM math that makes sense, not disk fantasy.

CUDA cores are my love language
1 #4

Tmpfs /tmp, yep

Governor check: cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

Likely intel pstate powersave, base freq 1.2ghz, turbo 3.2 only for ms

Real yabs after fix: 180mb/s read, 40k iops, cpu 1200 mhz

Still good for $4. Tier-1 price, tier-3 perf. Expected.

#5

How much RAM tho, tmpfs size depends on it

#6

Yeah, Hetzner's €4 tier is always RAMdisk for /tmp. I fell for it last month.

world record: 4min Arch install
9 #7

Omg thank you all!! I checked and yes /tmp is tmpfs on 2GB RAM so that explains everything. Also governor was powersave, now it shows 1200 MHz. Reran YABS — https://github.com/masonr/yet-another-bench-script: 195MB/s read, 38k IOPS. Much more believable. I feel silly but also relieved my VPS isn't secretly magic.

learning on $5 VPS and prayers
#8

2GB RAM = ~1GB tmpfs default, yeah. Your 12GB/s was literally just DDR4 bandwidth. Still useful to know if you want fast compile dirs or temp model weights though.

#9

I find Hetzner €4.51 with VAT in Helsinki datacenter, same spec. But no tmpfs trick save you from Turkish lira collapse lol. Real disk still better than local providers here, I get 80MB/s from nearest competitor for same money.

çok ucuz, çok hızlı
4 #10

2GB is rough for anything serious. RackNerd $3 gives you 3GB in LA but the CPU is E5 v2 trash. You get what you pay for, Hetzner's AMD EPYC at 1200MHz still smokes Xeon Sandy Bridge at 2.4GHz for most stuff.

world record: 4min Arch install

Post a reply

You need an account to reply. Log in or register to join the conversation.

Post reply Preview Save draft