This is the mail archive of the
systemtap@sourceware.org
mailing list for the systemtap project.
Re: get the mapping of <key, syscallname>
- From: Martin Hunt <hunt at redhat dot com>
- To: Li Guanglei <guanglei at cn dot ibm dot com>
- Cc: "systemtap at sourceware dot org" <systemtap at sourceware dot org>
- Date: Thu, 11 May 2006 11:14:20 -0700
- Subject: Re: get the mapping of <key, syscallname>
- Organization: Red Hat Inc.
- References: <44629BC3.7030505@cn.ibm.com>
On Thu, 2006-05-11 at 10:04 +0800, Li Guanglei wrote:
> Hi,
> One of my tapsets will log the syscall name got from
> CONTEXT->probe_point. But string printing is costly so I want to log
> the key of syscall name, and later the post-processing app in user
> space will figure out the syscall name represented by corresponding keys.
string printing is more expensive than it should be because the
translator emits unoptimized code that copies them too often. That will
probably be fixed in the future. Still, I wouldn't call it "costly".
Writing a binary key instead will save you little for what may be a
temporary advantage. I advise waiting on this.
Martin