Diff type: controls how diffs are rendered when you look at a patch which is different from the current content of the node which it patches, or when you are looking at a patch and you select the <Diff> link next to some other other patch in the patch list.
The diff types are hard to explain; you're better off just trying them all and seeing which one you'd like best as a default. You can always choose to see a diff rendered in some other style by selecting one of the links in the The Patch Is Different line near the top of the patch display.
Regex diff:? someone who understands this setting should explain it here.
Split diff:? someone who understands this setting should explain it here.
Deleted Code Style: Inserted Code Style: When viewing a diff, these bits of CSS markup are inserted to the code which has been deleted or added, respectively, by the patch, relative to the other compared version.
Strike deleted: If checked, deleted code will have <strike> markup applied to it when viewing a diff.
Number when possible: The only line numbering options are "Never" and "When possible". Use a value of -1 for Never, and 1 for When possible. The default is 1. This setting is used when rendering blocks of code.
Default ordering for Patch Lister:
Value is the same format as the order= param, which you can see in action in Patch Lister - all those A/D links in the header row of the list table.
It is a comma-separated list of strings of the form xY, where x is a column mnemonic and Y is either A for Ascending or D for Descending. The column mnemonics are:
p = Patch
f = For
lu = Last Updated
au = Author
ab = Applier ("Applied by")
ap = Applied (date/time)
r = Reason
The default seems to be pD.
Default limit,skip for Patch Lister:
Value is the same format as the limit= param, which you can see in action in Patch Lister - The line right above the list table, below the "Filter" button.
It is a comma-separated pair of integers limit,skip, or in other words, count,start: Patch lister will list count patches (at most), starting at number start (in a zero-based numbering system).
The start value is optional.
In setting this deafult value, you probably don't want to specify a start, but if you want to see something other than the default 50 patches per page, you can put your preferred count here.
Show session cache stats:
Unlike the above settings, this is not used when displaying patches. Rather, it causes session cache statistics for certain code calls to be displayed at the bottom of each page. See stdcontainer. What this data is actually meaningful for... Can anyone explain?