Clean code vs. efficiency

[Christopher Benson-Manica]

Yesterday I changed some code to use std::vectors and std::strings
instead of character arrays. My boss asked me today why I did it, and
I said that the code looks cleaner this way. He countered by saying
that he was regarded the dyanamic allocation that C++ STL classes
perform as being very inefficient. He also said that he wasn't
particularly interested in clean code (!). My question to the group:
In what situations, if any, would you use fast but hackish C-style
code in favor of the convenient STL classes? Would your answer change
if you were forced to use a questionable implementation (such as,
not-so-hypothetically, Borland 4)?

--
Christopher Benson-Manica | I *should* know what I'm talking about - if I
ataru(at)cybers pace.org | don't, I need to know. Flames welcome.

[Stephen Waits]

Claudio Puviani wrote:

That this happens in some -- maybe even most -- cases, doesn't make it a rule

Agree.

We have our own containers that are as good or better than STL (as it
pertains to us).

He also mentioned lots of other mostly retarded things they'd found.
Most were unbelievable stupid, but that's OT.

And specific to their particular code base.

These weren't specific to one code base. These were trends the Xbox AT
Group had noticed after optimizing several years worth of Xbox titles.

Anyway, most of them were dumb (or ignorant) enough that they had no
bearing on code base - they'd have slowed just about anything to a crawl.

--Steve

[Mabden]

"Default User" <fi********@boe ing.com.invalid > wrote in message
news:40******** *******@boeing. com.invalid...

Karl Heinz Buchegger wrote:

Christopher Benson-Manica wrote:

Yesterday I changed some code to use std::vectors and std::strings
instead of character arrays. My boss asked me today why I did it, and
I said that the code looks cleaner this way. He countered by saying
that he was regarded the dyanamic allocation that C++ STL classes
perform as being very inefficient.

Really?
Has he tried it?
Does he have some performance data?

Since when does the boss have to prove things to subordinates?

Christopher is the one who wants to introduce changes to the code base,
it's up to him to program it both ways and perform benchmark testing on
it. A nice boss would let him try that on company time, a hardheaded one
would suggest that weekends are made for such experiments.

I had a Boss once that explained the situation quite succinctly, "Don't do
work that doesn't show."

If you're not adding changes the user demands, then what are they paying you
for? Plus, any change can introduce bugs...

--
Mabden

[Thomas Matthews]

Default User wrote:

Karl Heinz Buchegger wrote:

Christopher Benson-Manica wrote:

Yesterday I changed some code to use std::vectors and std::strings
instead of character arrays. My boss asked me today why I did it, and
I said that the code looks cleaner this way. He countered by saying
that he was regarded the dyanamic allocation that C++ STL classes
perform as being very inefficient.

Really?
Has he tried it?
Does he have some performance data?

Since when does the boss have to prove things to subordinates?

Christopher is the one who wants to introduce changes to the code base,
it's up to him to program it both ways and perform benchmark testing on
it. A nice boss would let him try that on company time, a hardheaded one
would suggest that weekends are made for such experiments.

Brian Rodenborn

Thanks, Brian.

Unfortunately, I also have Christopher's attitude. I was nearly put on
probation for creating a new design when the team (company) said just
document the old code. Now, I know that I can do new designs as long
as I do the old stuff first then prove that my new stuff will benefit
the company more than the old stuff.
--
Thomas Matthews

C++ newsgroup welcome message:
http://www.slack.net/~shiva/welcome.txt
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Other sites:
http://www.josuttis.com -- C++ STL Library book
http://www.sgi.com/tech/stl -- Standard Template Library

[Thomas Matthews]

Christopher Benson-Manica wrote:

Yesterday I changed some code to use std::vectors and std::strings
instead of character arrays. My boss asked me today why I did it, and
I said that the code looks cleaner this way. He countered by saying
that he was regarded the dyanamic allocation that C++ STL classes
perform as being very inefficient. He also said that he wasn't
particularly interested in clean code (!). My question to the group:
In what situations, if any, would you use fast but hackish C-style
code in favor of the convenient STL classes? Would your answer change
if you were forced to use a questionable implementation (such as,
not-so-hypothetically, Borland 4)?

In embedded systems, we try not to use the Compiler's libraries unless
we have plenty of code space and variable (RAM) space. Many
applications have very little RAM to play with, so don't have a "heap"
or dynamic memory. Using the STL as it comes (with generic allocators)
would cause problems.

However, perhaps using the STL with custom allocators _may_ be a
safer route. I don't know on this part because the prevalent attitude
is not to use C++ in embedded systems. :-(
--
Thomas Matthews

C++ newsgroup welcome message:
http://www.slack.net/~shiva/welcome.txt
C++ Faq: http://www.parashift.com/c++-faq-lite
C Faq: http://www.eskimo.com/~scs/c-faq/top.html
alt.comp.lang.l earn.c-c++ faq:
http://www.raos.demon.uk/acllc-c++/faq.html
Other sites:
http://www.josuttis.com -- C++ STL Library book
http://www.sgi.com/tech/stl -- Standard Template Library

[Default User]

Thomas Matthews wrote:

Default User wrote:

Christopher is the one who wants to introduce changes to the code base,
it's up to him to program it both ways and perform benchmark testing on
it.

Unfortunately, I also have Christopher's attitude. I was nearly put on
probation for creating a new design when the team (company) said just
document the old code. Now, I know that I can do new designs as long
as I do the old stuff first then prove that my new stuff will benefit
the company more than the old stuff.

Right. Do your research and learn to present it in a way that the boss
doesn't become defensive.

Now, if you happen to be in a situation like I am currently, doing
software R&D, then exploring alternatives is generally encouraged. Even
if it turns out that what you tried blows, at least there's a datapoint
for the next time some bright young (ha!) engineer has the same idea.

I also have a boss who's not a software person, so she doesn't have
ideas about how things should be programmed. Of course our tech lead
does.

It all depends on your situation.

Brian Rodenborn

[jeffc]

"Christophe r Benson-Manica" <at***@nospam.c yberspace.org> wrote in message
news:c7******** **@chessie.cirr .com...

Yesterday I changed some code to use std::vectors and std::strings
instead of character arrays. My boss asked me today why I did it, and
I said that the code looks cleaner this way. He countered by saying
that he was regarded the dyanamic allocation that C++ STL classes
perform as being very inefficient. He also said that he wasn't
particularly interested in clean code (!). My question to the group:
In what situations, if any, would you use fast but hackish C-style
code in favor of the convenient STL classes?

Frankly, it sounds like your manager doesn't *really* know what he's talking
about. There is far, far more money wasted on fixing and customizing and
maintaining hard-to-read code than there is lost on inefficient code. Now
it just could be that your compiler does a crappy job with these things and
it is slow. But on the other hand, it still might not matter! (Does it
really matter to the user if something takes .03 seconds or .01 seconds?)

[jeffc]

"Default User" <fi********@boe ing.com.invalid > wrote in message
news:40******** *******@boeing. com.invalid...

Karl Heinz Buchegger wrote:

Christopher Benson-Manica wrote:

Yesterday I changed some code to use std::vectors and std::strings
instead of character arrays. My boss asked me today why I did it, and
I said that the code looks cleaner this way. He countered by saying
that he was regarded the dyanamic allocation that C++ STL classes
perform as being very inefficient.

Really?
Has he tried it?
Does he have some performance data?

Since when does the boss have to prove things to subordinates?

Who said his boss had to prove anything?

[Default User]

jeffc wrote:

"Default User" <fi********@boe ing.com.invalid > wrote in message
news:40******** *******@boeing. com.invalid...

Karl Heinz Buchegger wrote:

Christopher Benson-Manica wrote:
>
> Yesterday I changed some code to use std::vectors and std::strings
> instead of character arrays. My boss asked me today why I did it, and
> I said that the code looks cleaner this way. He countered by saying
> that he was regarded the dyanamic allocation that C++ STL classes
> perform as being very inefficient.

Really?
Has he tried it?
Does he have some performance data?

Since when does the boss have to prove things to subordinates?

Who said his boss had to prove anything?

Doesn't that flow from the questions I answered? What are those if not
requests for proof?

Brian Rodenborn