A Misleading Error While Testing HammerDB On Hekaton

Safe Words


This a short post about a sort of quirky error message I got while trying to run the TPC-C load test against SQL Server’s in-memory tables.

Error in Virtual User1: [Microsoft][ODBC Driver 17 for SQL Server][SQL Server]The integer value XXXXXXXXXXXX is out of range.

2020 10 08 14 35 50
chucked

A few of the tables would get created, but not all of them. It wasn’t obvious where that number was coming from, until I thought back to the setup.

In the build script, there’s a helpful looking line for you to adjust the hash bucket count that your indexes get created with.

2020 10 08 14 36 05
tinker tailor

I had set mine to a higher number, thinking it would help load speeds to have a bunch of buckets ready in there.

But the thing is, buried way down in the script, there’s already some math to pad the hash buckets for you.

2020 10 08 14 37 48
the salty bucket

If you’re in the mood to be totally underwhelmed, you should also run this test against Hekaton.

Thanks for reading!

Going Further


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2 thoughts on “A Misleading Error While Testing HammerDB On Hekaton

  1. Finally got around to running HammerDB 4.1
    Tried the flashy Hekaton switch and it failed to create the tables at your hash buckets value of 64 above
    1 works just fine

    I think ill call Hekaton “όχι εκατόn”
    Or, in the immortal word of Riddick “Not Furya”

    TPC-H
    My Disk-Based Database score on a HP Z5 was [388,000]
    Hekaton on the same hardware was [45,500 to about 90,000] – Jamie’s Cryin’
    On an Azure SQL G5 8Core 32GB 200GB instance (the default): [33,402] 10x slower- Not Gonna Cloud much

    Plus on Hekaton, I got lots of error 701 – not enough memory to run this query
    Nice

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