Re: pg_standby for 8.2 (with last restart point) - Mailing list pgsql-hackers

On Fri, Mar 28, 2008 at 10:30 AM, Gurjeet Singh <<a
href="mailto:singh.gurjeet@gmail.com">singh.gurjeet@gmail.com</a>>wrote:<br /><div class="gmail_quote"><blockquote
class="gmail_quote"style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><br
/>Iam still looking for comments on the correctness of this script and above mentioned procedure for running it on an
8.2.xrelease.<br /></blockquote></div><br />Well, I came across a serious bug in the script. Here's the corrected
versionof the perl script for anyone who might have picked up the script from here:<br /><br />(Am still looking for
anyfeedback on the correctness of the script; especially in the light of the recent possible bugs fixed on the server
side,related to recovery)<br /><br /><span style="font-family: courier new,monospace;"><script></span><br
style="font-family:courier new,monospace;" /><span style="font-family: courier new,monospace;">my @text = `</span><span
class="nfakPe"style="font-family: courier new,monospace;">pg_controldata</span><span style="font-family: courier
new,monospace;">.`; # here . represents the PGDATA, since the server is executing here.</span><br style="font-family:
couriernew,monospace;" /><span style="font-family: courier new,monospace;">my $line;</span><br style="font-family:
couriernew,monospace;" /><br style="font-family: courier new,monospace;" /><span style="font-family: courier
new,monospace;">my$time_line_id;</span><br style="font-family: courier new,monospace;" /><span style="font-family:
couriernew,monospace;"> my $redo_log_id;</span><br style="font-family: courier new,monospace;" /><span
style="font-family:courier new,monospace;">my $redo_rec_off;</span><br style="font-family: courier new,monospace;"
/><spanstyle="font-family: courier new,monospace;">my $wal_seg_bytes;</span><br style="font-family: courier
new,monospace;"/><span style="font-family: courier new,monospace;">my $redo_log_seg;</span><br style="font-family:
couriernew,monospace;" /><br style="font-family: courier new,monospace;" /><span style="font-family: courier
new,monospace;">foreach$line ( @text )</span><br style="font-family: courier new,monospace;" /><span
style="font-family:courier new,monospace;">{</span><br style="font-family: courier new,monospace;" /><span
style="font-family:courier new,monospace;">    $line = mychomp( $line );</span><br style="font-family: courier
new,monospace;"/><br style="font-family: courier new,monospace;" /><span style="font-family: courier
new,monospace;">   if( $line =~ m/Latest checkpoint's TimeLineID:\s*(([0-9])+)/ )</span><br style="font-family: courier
new,monospace;"/><span style="font-family: courier new,monospace;">     {</span><br style="font-family: courier
new,monospace;"/><span style="font-family: courier new,monospace;">        # decimal number</span><br
style="font-family:courier new,monospace;" /><span style="font-family: courier new,monospace;">        $time_line_id =
0+ $1;</span><br style="font-family: courier new,monospace;" /><span style="font-family: courier new,monospace;">   
}</span><brstyle="font-family: courier new,monospace;" /><span style="font-family: courier new,monospace;">    if(
$line=~ m/Latest checkpoint's REDO location:\s*(([0-9]|[A-F])+)\/</span><span style="font-family: courier
new,monospace;">(([0-9]|[A-F])+)/)</span><br style="font-family: courier new,monospace;" /><div class="ArwC7c ckChnd"
id="1fzd"><spanstyle="font-family: courier new,monospace;">    {</span><br style="font-family: courier new,monospace;"
/><spanstyle="font-family: courier new,monospace;">        # hexadecimal numbers</span><br style="font-family: courier
new,monospace;"/><span style="font-family: courier new,monospace;">         $redo_log_id = hex( $1 );</span><br
style="font-family:courier new,monospace;" /><span style="font-family: courier new,monospace;">        $redo_rec_off =
hex($3 );</span><br style="font-family: courier new,monospace;" /><span style="font-family: courier new,monospace;">   
}</span><brstyle="font-family: courier new,monospace;" /><br style="font-family: courier new,monospace;" /><span
style="font-family:courier new,monospace;">    if( $line =~ m/Bytes per WAL segment:\s*([0-9]+)/ )</span><br
style="font-family:courier new,monospace;" /><span style="font-family: courier new,monospace;">    {</span><br
style="font-family:courier new,monospace;" /><span style="font-family: courier new,monospace;">        # decimal
number</span><brstyle="font-family: courier new,monospace;" /><span style="font-family: courier new,monospace;">       
$wal_seg_bytes= $1;</span><br style="font-family: courier new,monospace;" /><span style="font-family: courier
new,monospace;">   }</span><br style="font-family: courier new,monospace;" /><span style="font-family: courier
new,monospace;">}</span><brstyle="font-family: courier new,monospace;" /><br style="font-family: courier
new,monospace;"/><span style="font-family: courier new,monospace;">$redo_log_seg = sprintf( "%d", $redo_rec_off /
$wal_seg_bytes);</span><br style="font-family: courier new,monospace;" /><br style="font-family: courier
new,monospace;"/><span style="font-family: courier new,monospace;">print "" . sprintf( "%08X%08X%08X", $time_line_id,
$redo_log_id,$redo_log_seg ) . "\n";</span><br style="font-family: courier new,monospace;" /><br style="font-family:
couriernew,monospace;" /><span style="font-family: courier new,monospace;"># Wrapper around Perl's chomp
function</span><brstyle="font-family: courier new,monospace;" /><span style="font-family: courier new,monospace;">sub
mychomp</span><brstyle="font-family: courier new,monospace;" /><span style="font-family: courier
new,monospace;">{</span><brstyle="font-family: courier new,monospace;" /><span style="font-family: courier
new,monospace;">   my ( $tmp ) = @_;</span><br style="font-family: courier new,monospace;" /><span style="font-family:
couriernew,monospace;">     chomp( $tmp );</span><br style="font-family: courier new,monospace;" /><span
style="font-family:courier new,monospace;">    return $tmp;</span><br style="font-family: courier new,monospace;"
/><spanstyle="font-family: courier new,monospace;">}</span><br style="font-family: courier new,monospace;" /><br
style="font-family:courier new,monospace;" /><span style="font-family: courier
new,monospace;"></script></span><brstyle="font-family: courier new,monospace;" /><font color="#888888"><br
/></font></div><brclear="all" /><br />-- <br />gurjeet[.singh]@EnterpriseDB.com<br />singh.gurjeet@{ gmail | hotmail |
indiatimes| yahoo }.com<br /><br />EnterpriseDB <a
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