G'Day Dan,
On Tue, Dec 04, 2007 at 03:46:50PM -0800, Dan Price wrote:
>
> I have been using Eric Kustarz's "nfstop" dtrace script to keep an eye on
> a server; the output looks like this:
Eric's script is going to become much easier with the stable NFS providers. :)
> host: 129.146.226.97 num nfs calls: 6
> host: 129.145.154.106 num nfs calls: 7
> host: 129.146.11.146 num nfs calls: 8
> host: 129.146.108.85 num nfs calls: 8
> host: 10.4.180.27 num nfs calls: 11
> host: 129.146.228.172 num nfs calls: 16
> host: 129.146.11.145 num nfs calls: 17
> host: 129.146.228.151 num nfs calls: 19
> host: 129.146.228.144 num nfs calls: 22
> ...
>
>
> While this is helpful, I'd much rather format the output as follows:
>
> HOST OPS
> 129.146.226.97 6
> 129.145.154.106 7
> 129.146.11.146 8
> 129.146.108.85 8
> 10.4.180.27 11
> 129.146.228.172 16
> 129.146.11.145 17
> 129.146.228.151 19
> 129.146.228.144 22
>
> Which to my eyes is a lot easier to process rapidly.
>
> The problem here is that the IP address is stored byte by byte in the
> aggregation, as follows:
>
> @hosts[self->sin_addr[0], self->sin_addr[1], self->sin_addr[2],
> self->sin_addr[3]] = count();
>
> (There is a similar clause for ipv6 addresses which I have omitted here).
>
> And so the printa() looks like this:
>
> printa("\nhost: %d.%d.%d.%d num nfs calls: [EMAIL PROTECTED]", @hosts)
>
> This would seem to make it fairly difficult to align the columns of output,
> unless I zero-fill each IP address (ugly). My initial thought was to trying
> something like this:
>
> s = sprintf("%d.%d.%d.%d", self->sin_addr[0], self->sin_addr[1],
> self->sin_addr[2], self->sin_addr[3]])
> @hosts[s] = count();
>
> ...
>
> printa("%20s\t\t%d")
>
> Unfortunately, there is no sprintf, I presume because printf processing
> happens
> up in userland. So I was wondering if there's a best practice here, or some
> other obvious way to cope with this problem?
I solved this once using a series of strjoin()s (see tcpsnoop.d in the
DTraceToolkit); but you really want to use inet_ntoa(), inet_ntoa6() or
inet_ntop(), which I added to DTrace several months ago (and to the DTrace
wiki about a week ago), for usage such as this.
The changes to nfstop would include something like this:
this->str4 = inet_ntoa(&((struct sockaddr_in *)self->ca)->sin_addr.S_un.S_addr);
[...]
this->str6 = inet_ntoa6(&((struct sockaddr_in6 *)self->ca)->sin6_addr);
Brendan
--
Brendan
[CA, USA]
_______________________________________________
dtrace-discuss mailing list
[email protected]
