you can try "sscomp" as a parameter to mminfo, eg:
legato # mminfo  -q client=myclient -r
'savetime(32),sscomp(32),sumsize,name' -t 'yesterday' -ot
          date     time                   ss completed             size name
            03/18/08 09:15:42 PM            03/18/08 09:18:29 PM 1218
KB SYSTEM DB:\
            03/18/08 09:15:44 PM            03/18/08 09:18:52 PM  15
MB SYSTEM STATE:\
            03/18/08 09:15:45 PM            03/18/08 09:18:59 PM  53 MB D:\
            03/18/08 09:16:36 PM            03/18/08 09:17:09 PM 259 MB C:\


Also, if you get savegrp reports as Keith noted, you'll get some of
the info you are looking for.  You'll have the group start and end
time and then details for each clients savesets. eg:

Start time:   Tue Mar 18 21:15:00 2008
End time:     Tue Mar 18 21:22:17 2008

--- Successful Save Sets ---

  myclient: SYSTEM FILES:\ level=skip, 0 KB 00:00:35      0 files
  myclient: SYSTEM DB:\ level=full, 1218 KB 00:02:49      7 files
  myclient: SYSTEM STATE:\ level=full, 15 MB 00:03:13     17 files
  myclient: D:\ level=incr,     53 MB 00:03:20     59 files

As you can see, each client shows duration times for the individual savesets.

To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type "signoff networker" in the body of the email. Please write to 
networker-request AT listserv.temple DOT edu if you have any problems with this 
list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER