We noticed our Azure SQL Server CPU spiking on user login (we may have been hit with a bot, but that type load is to be expected at certain times for us). When I ran the query execution plan, it seemed fine.

Then Azure was telling us that there was locking going on. I then dug into the MemberService code, and saw the following:

public IMember GetByUsername(string username)
{
    // TODO: Somewhere in here, whether at this level or the repository level, we need to add
    // a caching mechanism since this method is used by all the membership providers and could be
    // called quite a bit when dealing with members.

    using (var scope = ScopeProvider.CreateScope(autoComplete: true))
    {
        scope.ReadLock(Constants.Locks.MemberTree);
        var query = Query<IMember>().Where(x => x.Username.Equals(username));
        return _memberRepository.Get(query).FirstOrDefault();
    }
}

We are curious as to why the tree is being locked to query a user by username? Also, is there any plan to cache this? It seems like a high priority area to cache for any site that has members.

Thanks