Re: Fastest way to iterate over a persistence cache

[Stephen Darlington]

You may need to do the parallelism “manually.” Something like:

for (int p = 0; p < ignite.affinity("TEST").partitions(); p++) {
    ignite.compute().affinityRunAsync(Arrays.asList("TEST"), p, () -> {
        ScanQuery q = new ScanQuery()
                .setPartition(p);
        System.out.println(ignite.cache("TEST").query(q).getAll());
    });
}

Regards,
Stephen

> On 15 Apr 2021, at 17:52, Sebastian Macke <sebast...@macke.de> wrote:
> 
> Hi,
> 
> of course we are using SSDs, but 4kB is still a tiny amount, when you have
> to wait for the SSD read roundtrip every time. The CPU is idle at about
> 10%.. The Linux kernel does not seem to perform a readahead, probably
> because of the random access structure.
> 
> For some reason the QueryParallelism feature does not work either. No change
> in the speed.
> 
> Regards
> 
> Sebastian
> 
> 
> 
> 
> 
> 
> --
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