[tor-bugs] #16914 [Tor]: improve consensus download decompress performance

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#16914: improve consensus download decompress performance
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     Reporter:  teor         |      Owner:
         Type:  enhancement  |     Status:  new
     Priority:  normal       |  Milestone:
    Component:  Tor          |    Version:  Tor: 0.2.6.10
   Resolution:               |   Keywords:  TorCoreTeam201509 Post027Freeze
Actual Points:               |  Parent ID:
       Points:               |
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Comment (by teor):

 This modifies the estimate for every gzip decompression performed by tor.
 We could go two ways on this:
 * allow the caller to supply an estimate in a new
 tor_gzip_uncompress_estimate() (and leave existing callers as-is)
 * modify the estimate globally

 I will now check the range of compression ratios on tor directory files.

 I plan to use `gzip -9` as a proxy for tor_gzip_compress. Note that the
 gzip command generates file headers, but tor generates HTTP/[Tor/]TCP/IP
 headers. The difference is likely to be negligible for large files.

 And it's the largest files that matter for decompression speed and memory
 usage.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/16914#comment:2>
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