
Laggy phones and misleading benchmarks - tarasglek
http://taras.glek.net/post/Laggy-phones-and-misleading-benchmarks/
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sylocheed
Hi! I saw your post on Reddit, and had some reactions—I'm curious to see what
you think.

So you obviously have domain expertise and credibility in IO optimization and
your article is one of the better researched articles to discuss the topic of
Android UI "jank". I feel like there's more to the story than your thesis and
is ultimately not the whole conclusion.

Primarily—aside from citing some academic articles on SQLite IO impact on
Android performance, what I think is missing is a real-world connection from
the theory that IO is related to UI jank. And I think most particularly, you
cite the iPhone 7 and Pixel as having subpar random 4K write performance, even
though there is broad anecdotal consensus that those two flagship phones have
some of the smoothest, jank-free UI of the industry. I'm not suggesting that
this consensus is 100% correct, but it does provide a baseline for a gutcheck
and skeptical inquiry (side note: I really wish there was a way to objectively
test jank... no one's seemed to be able to get Google's WALT device
working...)

And interestingly, you note some midrange phones that appear to have better
measured IO performance... but what I think what is missing is evidence (even
anecdotal) to suggest that the measured higher IO performance of the Motorola
G4 or ZTE ZMax Pro actually translates to smoother performance, compared to
flagships with more poorly performing NAND. In fact, the AnandTech review the
author cites to for Motorola G4 4K write speed has this to say about
performance: "The Moto G4's performance hasn't impressed me in any respect.
... The performance issues aren't just limited to benchmarks. Motorola's
previous phones provided a smooth experience despite their limited
specifications, and the Moto G4 and G4 Plus are significantly jankier
throughout the UI, with even the simplest of ListViews stuttering at times."

If the Motorola G4 in fact does have weak UI performance and jank while having
" 7x better than the flagships" random 4k write performance, then I'm not sure
the known evidence supports your ultimate thesis yet. It seems more
investigation is warranted. Thoughts?

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tarasglek
I agree, proof would be nice. I don't know Android well enough to connect UI
pauses to IO. Suggestions are welcome

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sigi45
Ah man that is horrible. My Samsung S4 mini is only nearly 3 years old and
gets laggier and laggier.

The only reason right now to buy a new phone is that lag.

Would be nice if i wouldn't need to buy a new phone every 3 years because of
broken NAND and/or better io performance.

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tarasglek
I suspect if you buy G4 and better Motorola phones with good random write perf
and reserve 10-20% of space, they should last a long time.

This could be verified via benchmarks.

Point of my blog is that if people focus on the right benchmarks they can
select phones that will last longer before the lag.

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pawadu
> I found a great paper on how SQLite accounts for 90% of Android IO

So with only marginally better memory and cache management in SQLite we could
get old tired phones to fly?

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tarasglek
Injured old phones would be less laggy with slightly different SQLite setup. I
think one could further optimize android/sqlite interaction to make it more
efficient too.

