Re: [Patch 1/3] CLD: End-to-end verbosity

Jeff Garzik <[email protected]>
Newsgroups org.kernel.vger.hail-devel
Message-ID <[email protected]>
On 03/31/2010 08:43 PM, Pete Zaitcev wrote:
> diff --git a/server/server.c b/server/server.c
> index 3208e0f..2d68ee6 100644
> --- a/server/server.c
> +++ b/server/server.c
> @@ -55,7 +55,7 @@ static struct argp_option options[] = {
>   	  "Store database environment in DIRECTORY.  Default: "
>   	  CLD_DEF_DATADIR },
>   	{ "debug", 'D', "LEVEL", 0,
> -	  "Set debug output to LEVEL (0 = off, 2 = max)" },
> +	  "Set debug output to LEVEL (0 = off, 1 = debugging)" },
>   	{ "stderr", 'E', NULL, 0,
>   	  "Switch the log to standard error" },
>   	{ "foreground", 'F', NULL, 0,
> @@ -64,6 +64,8 @@ static struct argp_option options[] = {
>   	  "Bind to UDP port PORT.  Default: " CLD_DEF_PORT },
>   	{ "pid", 'P', "FILE", 0,
>   	  "Write daemon process id to FILE.  Default: " CLD_DEF_PIDFN },
> +	{ "verbose", 'v', NULL, 0,
> +	  "Enable the session-level verbosity" },
>   	{ "strict-free", 1001, NULL, 0,
>   	  "For memory-checker runs.  When shutting down server, free local "
>   	  "heap, rather than simply exit(2)ing and letting OS clean up." },


As is hinted by the current code's debugging switch being an integer 
'level' value, the server [and client?] has increasing levels of 
verbosity.  The debug levels are

	0: key messages affecting server operation, only
	1: debugging output enabled, sans per-packet output
	2: debugging output enabled, including per-packet output

ie. clearly ordered by increasing value == increased verbosity.

As is clearly illustrated when I cut the patch down to the above 
snippet, the user interface you have created gives the user two "knobs" 
for log verbosity, and it is not clear to a casual user which knob 
controls which sets of messages.  That makes for a -more- confusing user 
interface, because the user must constantly ask themselves the question 
"do I need debug?  or verbose?  I don't know!"

Additionally, this interface changes runs counter to other tools, which 
increase verbosity with added "-v" switches -- analagous to the existing 
integer-based debug level interface.

If it is truly your desire to permit fine-grained selection of certain 
classes of messages, then don't dick around!  Go ahead and create a 
bitmap "log mask" which permits fine-grained selection of various 
messages, much like netif_msg_* and netif_msg_init() in the kernel's 
include/linux/netdevice.h.

Having two switches, -d and -v, for different, undocumented classes of 
message just increases confusion.  Put yourself in the mind of a user 
trying to figure out which is which.

I readily admit the __internal implementation__ resulting from your 
patches is a useful cleanup, but at a macro level, it merely increases 
logging user interface confusion.

	Jeff
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.