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Update README.md

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@ -90,7 +90,11 @@ The json stream parser is threaded, using exactly two threads.
## Large files
If you are processing large files (e.g., 100 MB), it is likely that the performance of simdjson will be limited by page misses and/or page allocation. You will get best performance with large or huge pages. Under Linux, you can enable transparent huge pages with a command like `echo always > /sys/kernel/mm/transparent_hugepage/enabled` (root access may be required). We recommend that you report performance numbers with and without huge pages.
If you are processing large files (e.g., 100 MB), it is likely that the performance of simdjson will be limited by page misses and/or page allocation. [On some systems, memory allocation runs far slower than we can parse (e.g., 1.4GB/s).](https://lemire.me/blog/2020/01/14/how-fast-can-you-allocate-a-large-block-of-memory-in-c/)
You will get best performance with large or huge pages. Under Linux, you can enable transparent huge pages with a command like `echo always > /sys/kernel/mm/transparent_hugepage/enabled` (root access may be required). We recommend that you report performance numbers with and without huge pages.
Another strategy is to reuse pre-allocated buffers. That is, you avoid reallocating memory. You just allocate memory once and reuse the blocks of memory.
## Code usage and example