c# - Storing and retrieving large number of avatars just based on usernames? -

i want store large number (millions) of user avatars in file system. files must uniformly distributed in file system scales more files added.

the avatars 5-10kb in size images. application asp.net mvc (c#)

storing:

consider these following unique user ids: bob, mike, robert, johnson avatar names bob.jog, mike.jpg, robert.jpg, johnson.jpg

html elements render avatar:

<img class="avatar" src="www.xyz.com/getavatar?user=bob" /> <img class="avatar" src="www.xyz.com/getavatar?user=mike" /> 

this go getavatar controller action avatar physical location , write response buffer

current architecture:

[httppost]         public actionresult saveavatar(httppostedfile avatarimage, string user) {    //get md5 hash of user (bob=9f9d51bc70ef21ca5c14f307980a29d8)    //split md5 hash string folders (\9f\9d\51\bc\)    //save avatar @ path <file_server>\images\9f\9d\51\bc\bob.jpg }  [httpget]         public actionresult getavatar(string user) {    //get md5 hash of user (bob=9f9d51bc70ef21ca5c14f307980a29d8)    //find file location md5 hash (9f\9d\51\bc\)    //return <file_server>\images\9f\9d\51\bc\bob.jpg } 

am way off on this? if yes, how architect this?

i use userid (auto generated new uuid) of user database in case have store userid in tables have username

thanks reading

i haven't seen way of creating folder structure, however, thought interesting.

assuming have million of users, do, 1 million users x 10kb near 10gb, it's not store.

the problem is, how many users access @ same time? if it's lot, server can slow deliver these files, because server has handle millions of access already.

if had website millions of users, wouldn't store avatars , content in application server, use cdn(content delivery network) store images, or dedicated server uploading images, such avatar.mydomain.com, upload domain via wcf.