RE: I/O and db_file_multiblock_read_count

From: Matthew Zito <mzito_at_gridapp.com>
Date: Tue, 12 Dec 2006 12:50:34 -0500
Message-ID: <C0A5E31718FC064A91E9FD7BE2F081B199CACD@exchange.gridapp.com>

Nono, its just that on Linux, let's say, cat S.dbf > /dev/null is fast, but an strace will show that its actually doing a stream of write()s to the device. On solaris, it does something like (horrible perl-ish pseudocode):  

if ( dest == /dev/null) {

    exit 0;
} else {

    write(contents, dest);
}    

Matt

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        From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Kevin Closson

	Sent: Tuesday, December 12, 2006 12:45 PM
	To: oracle-l
	Subject: RE: I/O and db_file_multiblock_read_count
	
	
	what? can't dump junk in the bit bucket on Sol? I must not be

gettign your point

---

		From: Matthew Zito [mailto:mzito_at_gridapp.com] 
		Sent: Tuesday, December 12, 2006 9:40 AM
		To: kevinc_at_polyserve.com; oracle-l
		Subject: RE: I/O and db_file_multiblock_read_count
		
		
		/dev/null is hard, as some OS'es, solaris notably, do

evil tricks with certain utilities (like cat something to /dev/null - it returns immediately). Not sure about dd

---

                        From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Kevin Closson                         

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Received on Tue Dec 12 2006 - 11:50:34 CST