Re: bytea vs. pg_dump - Mailing list pgsql-hackers

From Bernd Helmle
Subject Re: bytea vs. pg_dump
Date
Msg-id 6DDBA33E4F768956C7066E0A@teje
Whole thread Raw
In response to Re: bytea vs. pg_dump  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: bytea vs. pg_dump  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
--On Dienstag, Mai 05, 2009 10:00:37 -0400 Tom Lane <tgl@sss.pgh.pa.us> 
wrote:

>
> Seems like the right response might be some micro-optimization effort on
> byteaout.

Hmm looking into profiler statistics seems to second your suspicion:

Normal COPY shows:
 %   cumulative   self              self     totaltime   seconds   seconds    calls   s/call   s/call  name31.29
81.38   81.38   134487     0.00     0.00  CopyOneRowTo22.88    140.89    59.51   134487     0.00     0.00
byteaout13.44   175.84    34.95 3052797224     0.00     0.00 
 
appendBinaryStringInfo12.10    207.32    31.48 3052990837     0.00     0.00  CopySendChar 8.45    229.31    21.99
3052797226    0.00     0.00  enlargeStringInfo 3.90    239.45    10.14    55500     0.00     0.00  pglz_decompress 3.28
  247.97     8.52        3     2.84     2.84  appendStringInfoChar 1.82    252.71     4.74   134489     0.00     0.00
resetStringInfo1.72    257.18     4.47                             copy_dest_destroy 0.27    257.89     0.71  5544679
 0.00     0.00 
 
hash_search_with_hash_value 0.09    258.13     0.24 13205044     0.00     0.00  LWLockAcquire 0.08    258.35     0.22
13205044    0.00     0.00  LWLockRelease
 

COPY BINARY generates:
time   seconds   seconds    calls   s/call   s/call  name73.70      9.05     9.05    55500     0.00     0.00
pglz_decompress6.03      9.79     0.74  5544679     0.00     0.00 
 
hash_search_with_hash_value 2.93     10.15     0.36 13205362     0.00     0.00  LWLockAcquire 1.87     10.38     0.23
13205362    0.00     0.00  LWLockRelease
 

This is PostgreSQL 8.3.7 btw.

--  Thanks
                   Bernd


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