如何在iOS 9.3中加快HKStatisticsCollectionQuery? [英] How to speed up HKStatisticsCollectionQuery in iOS 9.3?

问题描述

在iOS 9.3中，HKStatisticsCollectionQuery似乎非常慢.一年前每小时一次返回有效卡路里的统计信息可能需要40秒钟以上的时间.

It seems HKStatisticsCollectionQuery is incredibly slow in iOS 9.3. It can take upwards of 40 seconds to return hourly statistics for a year for active calories where it took 1 or less before.

let predicate = HKQuery.predicateForSamplesWithStartDate(anchorDate, endDate: endDate, options: [])
    let query = HKStatisticsCollectionQuery(quantityType: quantityType,
        quantitySamplePredicate: predicate,
        options: statisticOptions,
        anchorDate: anchorDate,
        intervalComponents: interval)

推荐答案

经过数小时的反复试验，我发现HKStatisticsCollectionQuery不是线程友好的.为了解决问题，我使用了以下异步NSOperation: https://gist.github.com/calebd/93fa347397cec5f88233

After many hours of trial and error I have found that HKStatisticsCollectionQuery is not thread friendly. In order to solve the problem I used this async NSOperation: https://gist.github.com/calebd/93fa347397cec5f88233

当然还有一个NSOperationQueue，以强制HKStatisticsCollectionQuerys同步执行.一旦完成此操作，每个查询将花费不到半秒钟的时间.

And of course an NSOperationQueue in order to force the HKStatisticsCollectionQuerys to be performed synchronously. Once I did that each query took less than half a second.

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