[tor-bugs] #4626 [Tor Directory Authority]: Very high cpu usage for gabelmoo running master

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#4626: Very high cpu usage for gabelmoo running master
-------------------------------------+--------------------------------------
 Reporter:  Sebastian                |          Owner:                    
     Type:  defect                   |         Status:  needs_review      
 Priority:  major                    |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Directory Authority  |        Version:                    
 Keywords:                           |         Parent:                    
   Points:                           |   Actualpoints:                    
-------------------------------------+--------------------------------------

Comment(by Sebastian):

 So, unfortunately the patch doesn't seem to work for me, not even when I
 applied it directly on top of the (suspected) faulty commit and ran that.

 But here's something very interesting: this is a profile of the commit
 directly before 44619d5e4, where the cpu usage stays below 10% typically

 {{{
 288491   51.1032  tor                      tor
 bn_mul_mont
 31541     5.5872  tor                      tor
 _x86_64_AES_encrypt_compact
 30061     5.3250  libz.so.1.2.5            tor
 deflate_slow
 18985     3.3630  libz.so.1.2.5            tor
 build_tree
 14140     2.5048  tor                      tor
 sha1_block_data_order
 13043     2.3104  libc-2.11.2.so           tor
 _int_malloc
 9262      1.6407  tor                      tor
 _x86_64_AES_decrypt_compact
 8564      1.5170  tor                      tor
 tor_memeq
 7717      1.3670  tor                      tor
 BN_mod_exp_mont_consttime
 6585      1.1665  tor                      tor
 connection_bucket_refill
 5682      1.0065  libc-2.11.2.so           tor
 strcasecmp
 3646      0.6459  libz.so.1.2.5            tor
 fill_window
 3573      0.6329  libc-2.11.2.so           tor                      memcpy
 3544      0.6278  libz.so.1.2.5            tor
 compress_block
 3124      0.5534  libc-2.11.2.so           tor                      memmem
 3007      0.5327  tor                      tor
 digestmap_get
 2703      0.4788  tor                      tor
 BN_mod_mul_montgomery
 2394      0.4241  libz.so.1.2.5            tor
 send_tree
 2268      0.4018  libz.so.1.2.5            tor
 _tr_flush_block
 2106      0.3731  libc-2.11.2.so           tor
 _int_free
 2090      0.3702  tor                      tor
 digestmap_iter_get
 1935      0.3428  libc-2.11.2.so           tor                      memset
 1902      0.3369  tor                      tor
 bn_mul_add_words
 1870      0.3313  tor                      tor
 MOD_EXP_CTIME_COPY_TO_PREBUF
 1727      0.3059  tor                      tor
 aes_crypt_inplace
 1588      0.2813  tor                      tor
 md5_block_asm_data_order
 1522      0.2696  tor                      tor
 dirserv_orconn_tls_done
 1488      0.2636  tor                      tor
 buf_datalen
 1469      0.2602  libc-2.11.2.so           tor
 malloc_consolidate
 1348      0.2388  tor                      tor
 ssl_cipher_apply_rule
 1251      0.2216  libc-2.11.2.so           tor                      free
 1122      0.1988  tor                      tor
 connection_or_set_bad_connections
 1089      0.1929  libc-2.11.2.so           tor
 vfprintf
 1077      0.1908  libc-2.11.2.so           tor                      malloc
 1063      0.1883  libz.so.1.2.5            tor
 adler32
 1062      0.1881  libevent-2.1.so.1.0.0    tor
 event_base_loop
 930       0.1647  tor                      tor                      BN_div
 893       0.1582  tor                      tor
 ap_stream_wants_exit_attention
 886       0.1569  tor                      tor
 AES_cbc_encrypt
 882       0.1562  tor                      tor
 EVP_MD_CTX_cleanup
 }}}

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4626#comment:12>
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