On Fri, May 29, 2020 at 05:25:47PM -0400, Thara Gopinath wrote: > > > Hi Eric, > > > > > > I tested this manually on db845c, sm8150-mtp and sm8250-mtp.(I added the dts > > > file entries for 8150 and 8250). > > > > > > I also ran OsBench test case createfiles[1] on the above platforms. > > > Following are the results on a non encrypted and encrypted directory on the > > > same file system(lower the number better) > > > > > > 8250-MTP 8150-MTP DB845 > > > > > > nonencrypt_dir(us) 55.3108954 26.8323124 69.5709552 > > > encrypt_dir(us) 70.0214426 37.5411254 92.3818296 > > > > > > > > > > > > 1. https://github.com/mbitsnbites/osbench/blob/master/README.md > > > > > > > Great, thanks for testing. > > > > Note that the benchmark you ran (creating many small files, then deleting them) > > mostly tests the performance of filenames encryption and directory operations, > > not file contents encryption. Inline encryption is only used for file contents. > > > > In fact, since that benchmark doesn't sync the files before deleting them, there > > is no guarantee that any file contents are actually written to disk, and hence > > no guarantee that inline encryption got used at all. > > Hi Eric, > > The results are particularly interesting if you think a sync is not > happening. You can check the source code (https://github.com/mbitsnbites/osbench/blob/master/src/create_files.c). There's no sync. > There should not be any performance regression in this case > between the two directories. That's not true; the filenames still need to be encrypted. Filenames encryption happens right away, not later when the pages are written to disk. Contents encryption works differently. > I can try some reading/writing performance tests rather than creating files > testing. > > > > It would be more relevant to test the performance of reading/writing file data. > > > > Also, did you try doing any correctness tests? (See what I suggested earlier.) > > I did correctness test as part of manual tests by diffing the content of the > copied files and verifying them. I did not run any other tests you > mentioned. Feel free to add my Tested-by in the next version you send out. > Okay, thanks! - Eric