The high probability of a disk read being necessary for each insert makes this scenario prone to poor performance.

对于每次的 insert，需要读磁盘的概率如此之高，使得这种场景往往性能很差。

youdao

The compact option magically makes the boot process quicker by merging adjacent disk read requests into a single request.

compact 选项可以大大加速引导过程，它会将连续的读磁盘的请求合并为一个单独的请求。

youdao

Of course, fetching images from disk is slower than loading from memory and should be done in a background thread, as disk read times can be unpredictable.

当然，从磁盘上获取这些图片要比从内存中加载慢，并且由于磁盘读取时间是不可预知的，所以也应该在后台进程中完成。

youdao

So as the particles on the disk that get the current in the read/write head moving put together millions of these magnetized segments and you've got a file.

通过读写头你就可以得到每个粒子的极性,如果把这些上百万粒子的信息,汇聚要一起就够成了一个文件。

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As the name suggests, databases are held in memory, not on disk, which significantly reduces the read time.

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The team is already thinking of applications for metamaterials as read-heads for future generations of hard-disk drives or optical modulators for communications.

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On previous iOS releases, when your app performed a coordinated read operation on a file or package and the iCloud daemon noticed that there was a newer version of the item available, the coordinated read operation blocked until the newer version of the item was downloaded and written to the disk.

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