mongodb - mongdb index does not work properly -

-

environment

10.10.109.131:23000   =>   shard000 10.10.109.131:23001   =>   shard001 10.10.111.251:23000   =>   shard000 10.10.111.251:23001   =>   shard001 10.10.97.197:23000    =>   shard000 10.10.97.197:23001    =>   shard001

phenomenon

view abnormally high in system.profile table scan, explain query again found table scan return normal

issue sql:

db.followers.find({"$and":[{"$or":[{"vaild":0},{"vaild":null}]},{"from":{"$in":[576893,2095602,1184292,650082,1373126,875232,815151,556585,1391458,813307,600211,2273636,106322,2206656,804217]}},{"to":1600312},{"$or":[{"vaild":null},{"vaild":0}]}]})

system.profile

      "op" : "query",       "ns" : "chuyesocial.followers",       "query" : {         ...       },       "ntoreturn" : 0,       "ntoskip" : 0,       "nscanned" : 424277,       "nscannedobjects" : 424263,

explain

shard001:primary> db.followers.find({"$and":[{"$or":[{"vaild":0},{"vaild":null}]},{"from":{"$in":[576893,2095602,1184292,650082,1373126,875232,815151,556585,1391458,813307,600211,2273636,106322,2206656,804217]}},{"to":1600312},{"$or":[{"vaild":null},{"vaild":0}]}]}).explain() {     "queryplanner" : {         "plannerversion" : 1,         "namespace" : "chuyesocial.followers",         "indexfilterset" : false,         "parsedquery" : {             ...         },     "executionstats" : {         "executionsuccess" : true,         "nreturned" : 13,         "executiontimemillis" : 4,         "totalkeysexamined" : 17,         "totaldocsexamined" : 17,         "executionstages" : {             "stage" : "keep_mutations",             "nreturned" : 13,             "executiontimemillisestimate" : 0,             "works" : 20,             "advanced" : 13,             "needtime" : 4,             "needfetch" : 1,             "savestate" : 5,             "restorestate" : 5,             "iseof" : 1,             "invalidates" : 0,              }         } }

index information

"_id_" : 37486960, "from_1__id_1" : 69896624,  （sharedkey） "to_1" : 37560544

other ：there 2 machines in cluster cpu 100% of cases


Comments

Post a Comment

Popular posts from this blog

c# - Better 64-bit byte array hash -

-
i need hash algorithm produces 64-bit hash code ( long ) fewer collisions string.gethashcode() , fast (no expensive calls cryptographic functions). here's implementation of fnv still shows 3% of collisions after testing 2 million random strings. need number way lower. void main() { const string chars = "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz!#@$%^&*()_+}{\":?><,./;'[]0123456789\\"; const int n = 2000000; var random = new random(); var hashes = new hashset<long>(); int collisions = 0; for(int = 0; < n; i++) { var len = random.next(chars.length); var str = new char[len]; (int j = 0; j < len; j++) { str[j] = chars[random.next(chars.length)]; } var s = new string(str); if(!hashes.add(get64bithash( s ))) collisions++; } console.writeline("collision percentage after " + n + " random strings: " + ((doubl
Read more

webrtc - Which ICE candidate am I using and why? -

-
[questions in bold below] i have setup kurento media server 5.1.3 in datacenter behind firewall running os ubuntu 14.04. has 2 network cards: 222.222.222.222 (eth0 - private ip) 111.111.111.111 (eth1 - public ip) attached below sdp (setremotedescription) when browser connected kurento media server type: answer, sdp: v=0 o=- 5487318114793304426 0 in ip4 0.0.0.0 s=kurento media server c=in ip4 0.0.0.0 t=0 0 a=group:bundle audio video m=audio 59068 rtp/savpf 111 0 c=in ip4 111.111.111.111 a=rtpmap:111 opus/48000/2 a=rtpmap:0 pcmu/8000 a=sendrecv a=rtcp:59068 in ip4 111.111.111.111 a=rtcp-mux a=ssrc:669011897 cname:user39019747@host-6e83e4c2 a=extmap:3 http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time a=mid:audio b=as:20 a=ice-ufrag:ymdk a=ice-pwd:lylifk5ueqzpwm91ddj37e a=fingerprint:sha-256 ff:0f:81:8c:41:4e:b4:b6:c6:d8:36:f3:d6:5f:09:fd:5f:af:13:b3:9d:fc:12:66:ac:f3:56:d6:5b:0a:73:5d a=candidate:1 1 udp 2013266431 111.111.111.111 55239 typ host a=candidate:2 1 udp
Read more

php - Zend Framework / Skeleton-Application / Composer install issue -

-
i trying create zend framework application using skeleton in netbeans. when run composer install, following error message: "c:\php\php.exe" "c:\composer\composer.phar" "--ansi" "--no-interaction" "update" "--dev" using deprecated option "dev". dev packages installed default now. loading composer repositories package information updating dependencies (including require-dev) requirements not resolved installable set of packages. problem 1 - package requires php >=5.5 php version (5.4.42) not satisfy requirement. problem 2 - installation request zendframework/zendframework 2.5.1 -> satisfiable zendframework/zendframework[2.5.1]. - zendframework/zendframework 2.5.1 requires php >=5.5 -> php version (5.4.42) not satisfy requirement. done. apparently, zend framework only needs php 5.3+ contradicts above. need use php 5.4. my composer.json following: { "name": "
Read more