{"action":"created","issue":{"url":"https://api.github.com/repos/monero-project/bitmonero/issues/724","repository_url":"https://api.github.com/repos/monero-project/bitmonero","labels_url":"https://api.github.com/repos/monero-project/bitmonero/issues/724/labels{/name}","comments_url":"https://api.github.com/repos/monero-project/bitmonero/issues/724/comments","events_url":"https://api.github.com/repos/monero-project/bitmonero/issues/724/events","html_url":"https://github.com/monero-project/bitmonero/issues/724","id":140627332,"number":724,"title":"Crash in mdb_cursor_get while syncing","user":{"login":"laanwj","id":126646,"avatar_url":"https://avatars.githubusercontent.com/u/126646?v=3","gravatar_id":"","url":"https://api.github.com/users/laanwj","html_url":"https://github.com/laanwj","followers_url":"https://api.github.com/users/laanwj/followers","following_url":"https://api.github.com/users/laanwj/following{/other_user}","gists_url":"https://api.github.com/users/laanwj/gists{/gist_id}","starred_url":"https://api.github.com/users/laanwj/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/laanwj/subscriptions","organizations_url":"https://api.github.com/users/laanwj/orgs","repos_url":"https://api.github.com/users/laanwj/repos","events_url":"https://api.github.com/users/laanwj/events{/privacy}","received_events_url":"https://api.github.com/users/laanwj/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":1,"created_at":"2016-03-14T10:00:38Z","updated_at":"2016-03-14T10:08:55Z","closed_at":null,"body":"Up to three times now I've had crashes (SIGSEGV) during sync. \r\n\r\n- Progress is 678888/995957, but this appears to be happening randomly.\r\n- This happens while catching up an old node. I've converted the old block chain using  `blockchain_export`/`blockchain_import`.\r\n- System: `Ubuntu 14.04.4 LTS` VM, 64-bit, 8GB memory, 8 cores, still plenty of HD space left\r\n- HEAD: 5843f89364691788843d3661a2b1cdb1651168da, compiled in `RelWithDebInfo` mode\r\n\r\ngdb output (#1-#5):\r\n```\r\nProgram received signal SIGSEGV, Segmentation fault.\r\n[Switching to Thread 0x7ffd30f8c700 (LWP 28657)]\r\nbash: mail: command not found\r\n0x00000000008122e1 in mdb_cursor_get (mc=0x7ffd181af840, key=0x7ffd30f89720, data=0x0, op=MDB_SET)\r\n    at /home/ubuntu/bitmonero/external/db_drivers/liblmdb/mdb.c:6906\r\n6906            if (mc->mc_txn->mt_flags & MDB_TXN_BLOCKED)\r\n(gdb) bt\r\n#0  0x00000000008122e1 in mdb_cursor_get (mc=0x7ffd181af840, key=0x7ffd30f89720, data=0x0, op=MDB_SET)\r\n    at /home/ubuntu/bitmonero/external/db_drivers/liblmdb/mdb.c:6906\r\n#1  0x00000000007fa83d in cryptonote::BlockchainLMDB::block_exists (this=0x2a3f140, h=...)\r\n    at /home/ubuntu/bitmonero/src/blockchain_db/lmdb/db_lmdb.cpp:1349\r\n#2  0x000000000072599f in cryptonote::Blockchain::have_block (this=0x2a1abc0, id=...)\r\n    at /home/ubuntu/bitmonero/src/cryptonote_core/blockchain.cpp:1847\r\n#3  0x0000000000750c0c in cryptonote::core::have_block (this=<optimized out>, id=...)\r\n    at /home/ubuntu/bitmonero/src/cryptonote_core/cryptonote_core.cpp:853\r\n#4  0x000000000068e44d in cryptonote::t_cryptonote_protocol_handler<cryptonote::core>::handle_response_chain_entry (this=0x2a1aa10,\r\n    command=<optimized out>, arg=..., context=...) at /home/ubuntu/bitmonero/src/cryptonote_protocol/cryptonote_protocol_handler.inl:765\r\n#5  0x000000000068474e in operator() (a3=..., a2=..., a1=2007, p=0x2a1aa10, this=0x7ffd30f89e40)\r\n    at /usr/include/boost/bind/mem_fn_template.hpp:393\r\n```\r\nFull gdb traceback can be found here:\r\nhttp://0bin.net/paste/pqduymi1W8k9cbZY#QkhwEmaE1oxMAJpke32hpEjeiXxhmMrhXm8qY-gqRQE\r\n"},"comment":{"url":"https://api.github.com/repos/monero-project/bitmonero/issues/comments/196236676","html_url":"https://github.com/monero-project/bitmonero/issues/724#issuecomment-196236676","issue_url":"https://api.github.com/repos/monero-project/bitmonero/issues/724","id":196236676,"user":{"login":"hyc","id":306354,"avatar_url":"https://avatars.githubusercontent.com/u/306354?v=3","gravatar_id":"","url":"https://api.github.com/users/hyc","html_url":"https://github.com/hyc","followers_url":"https://api.github.com/users/hyc/followers","following_url":"https://api.github.com/users/hyc/following{/other_user}","gists_url":"https://api.github.com/users/hyc/gists{/gist_id}","starred_url":"https://api.github.com/users/hyc/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/hyc/subscriptions","organizations_url":"https://api.github.com/users/hyc/orgs","repos_url":"https://api.github.com/users/hyc/repos","events_url":"https://api.github.com/users/hyc/events{/privacy}","received_events_url":"https://api.github.com/users/hyc/received_events","type":"User","site_admin":false},"created_at":"2016-03-14T10:08:55Z","updated_at":"2016-03-14T10:08:55Z","body":"when it crashes there, can you \"print *mc\" and paste that output too?"}}