>> Date: Mon, 5 Feb 2024 09:48:21 +0100 >> From: opensslmailing <mailto:opensslmailing@xxxxxx> >> To: mailto:openssl-users@xxxxxxxxxxx >> Subject: Build Options for maximum performance of SHA256 digest >> calculation >> Message-ID: <mailto:76163372.20240205094821@xxxxxx> >> Content-Type: text/plain; charset=us-ascii >> I want to build openssl for Windows to achieve best possible performance on >> my machine (Core i5 6500) of SHA256 digest calculation for large files in a >> C++ program. What options do I have to use to achieve this? >> P.S. Currently my program calculates about 330 Mibyte/s whereas other programs >> using OpenSSL reach about 400 MiByte/s on the same machine with the same file > I don't think this is really on-topic for this list, but some suggestions for > things to investigate: > - How big is the file? > - How are you reading the file (istream, fopen as text, fopen as binary, read, > memory map)? > - How are the other programs reading it? > - What platform are you running on? What compiler are you using? > - When you build OpenSSL, are you specifying compiler flags to generate code for > modern processors only? > Martin Bonner Hello, - the file is 4 GiByte of size - I'm reading the file using OpenSSL BIO mechanism with the "rb" option, so read as binary - I don't know how the other program (btw. it is fchash from the FastCopy program) reads the file - The platform is Windows 10 64 Bit. The compiler is Visual Studio 2022 - I'm using the following line: perl Configure VC-WIN64A --prefix=<respectivedirectory> --openssldir=<respectivedirectory> no-shared > Any email and files/attachments transmitted with it are intended > solely for the use of the individual or entity to whom they are > addressed. If this message has been sent to you in error, you must > not copy, distribute or disclose of the information it contains. > Please notify Entrust immediately and delete the message from your system.
