I would like to know if there is any difference, in terms of efficiency (i.e. less use of server resources) in performing 301 redirects using .htaccess or using the wp_safe_redirect feature of Wordpress? (which would be implemented via a plugin).
I don't mind putting the redirects into the .htaccess file by hand. But, if there is no greater overhead having a plug-in do the redirects (using wp_safe_redirect) then I'd rather go that route for the sake of simplicity (for other site admins).
Can anyone suggest which of these methods would have the least impact on the server?
After-thoughts / Answer
Considering the points made by both CYBMETA and Mark Kaplun, I get the impression the answer to my question is not a black and white one. I now understand it depends on many factors, and in most usage scenarios may make very little practical difference whether I use .htaccess or a plug-in.
A plug-in provides ease-of-use, but will have some degree of added overhead for the PHP to execute, and for the Wordpress core to load twice in order to deal with the redirect, and then deal with rendering the page. I realise that on an adequately configured server, this is unlikely to create a significant performance hit, unless the site is very busy and the redirected URIs account for a significant number of the site hits. I understand using .htaccess for the redirections means additional lines in the .htaccess have to be parsed for every resource request to the site, whether it's for the redirect URIs or not. Again, on an adequate server, that should have minimal real world impact. Using a plug-in is certainly more convenient for the end user, if numerous redirects need to be set up over time.
So, with these understandings in mind, I am not able to check either answer as the "accepted answer". I accept them both on their own merits, and have marked them up accordingly.