Re: Do we want a hashset type?

On 6/7/23 16:21, Joel Jacobson wrote:
> On Tue, Jun 6, 2023, at 13:20, Tomas Vondra wrote:
>> it cuts the timing to about 50% on my laptop, so maybe it'll be ~300ms
>> on your system. There's a bunch of opportunities for more improvements,
>> as the hash table implementation is pretty naive/silly, the on-disk
>> format is wasteful and so on.
>>
>> But before spending more time on that, it'd be interesting to know what
>> would be a competitive timing. I mean, what would be "good enough"? What
>> timings are achievable with graph databases?
>
> Your hashset is now almost exactly as fast as the corresponding roaringbitmap query, +/- 1 ms on my machine.
>

Interesting, considering how dumb the the hash table implementation is.

> I tested Neo4j and the results are surprising; it appears to be significantly *slower*.
> However, I've probably misunderstood something, maybe I need to add some index or something.
> Even so, it's interesting it's apparently not fast "by default".
>

No idea how to fix that, but it's rather suspicious.

regards

--
Tomas Vondra
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