[Veritas-bu] Max Fragment size
2004-02-17 11:53:49
This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.
------_=_NextPart_001_01C3F576.9D92B750
Content-Type: text/plain;
charset="iso-8859-1"
Each fragment is separately tracked in the catalog so having chunks too
small makes for larger catalogs. I think there's some header information
on-tape per fragment, too, so backup sizes might increase a bit.
Still, I think fragments are a big improvement to restore times are are well
worth it. 2 to 4 Gig seems to be a common suggested size.
-M
-----Original Message-----
From: Dave Markham [mailto:dave.markham AT icl DOT net]
Sent: Tuesday, February 17, 2004 4:50 AM
To: veritas-bu AT mailman.eng.auburn DOT edu
Subject: [Veritas-bu] Max Fragment size
I have seen in a few docs about setting this max fragment size to say 2 gig
or anything less than the max file size your OS can handle. How I understand
it is that this will then improve restore times as it can skip along these 2
gig chunks until it finds the section it needs and then begin a read through
of that chunk to find the files needed and start restore.
My question is 1. Am I right in my thinking? and 2. What would be the
downside to this? If it improves restore times what reason is there to not
set it?
Thanks
Environments:-
Netbackup 3.2, Solaris 8 Using SUN L1000 4 DLT 7000 tape units
Netbackup 4.5 FP6 Solaris 8 Using SUN L25 and LTO drive
Dave
------_=_NextPart_001_01C3F576.9D92B750
Content-Type: text/html;
charset="iso-8859-1"
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
<META content="MSHTML 6.00.2800.1400" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV><SPAN class=311195216-17022004><FONT face=Arial color=#0000ff size=2>Each
fragment is separately tracked in the catalog so having chunks too small makes
for larger catalogs. I think there's some header information on-tape per
fragment, too, so backup sizes might increase a bit.</FONT></SPAN></DIV>
<DIV><SPAN class=311195216-17022004><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=311195216-17022004><FONT face=Arial color=#0000ff
size=2>Still,
I think fragments are a big improvement to restore times are are well worth
it. 2 to 4 Gig seems to be a common suggested size.</FONT></SPAN></DIV>
<DIV><SPAN class=311195216-17022004><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=311195216-17022004><FONT face=Arial color=#0000ff
size=2>-M</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> Dave Markham
[mailto:dave.markham AT icl DOT net]<BR><B>Sent:</B> Tuesday, February 17,
2004 4:50
AM<BR><B>To:</B> veritas-bu AT mailman.eng.auburn DOT edu<BR><B>Subject:</B>
[Veritas-bu] Max Fragment size<BR><BR></FONT></DIV>
<DIV><FONT face=Arial size=2>I have seen in a few docs about setting this max
fragment size to say 2 gig or anything less than the max file size your OS
can
handle. How I understand it is that this will then improve restore times as
it
can skip along these 2 gig chunks until it finds the section it needs and
then
begin a read through of that chunk to find the files needed and start
restore.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>My question is 1. Am I right in my thinking? and
2. What would be the downside to this? If it improves restore times what
reason is there to not set it?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Environments:-</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Netbackup 3.2, Solaris 8 Using SUN L1000 4 DLT
7000 tape units</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Netbackup 4.5 FP6 Solaris 8 Using SUN L25 and
LTO
drive</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Dave</FONT></DIV></BLOCKQUOTE></BODY></HTML>
------_=_NextPart_001_01C3F576.9D92B750--
|
|
|