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-rw-r--r--db/repl/consensus.cpp124
1 files changed, 66 insertions, 58 deletions
diff --git a/db/repl/consensus.cpp b/db/repl/consensus.cpp
index 1519c26..f764abe 100644
--- a/db/repl/consensus.cpp
+++ b/db/repl/consensus.cpp
@@ -19,9 +19,9 @@
#include "rs.h"
#include "multicmd.h"
-namespace mongo {
+namespace mongo {
- class CmdReplSetFresh : public ReplSetCommand {
+ class CmdReplSetFresh : public ReplSetCommand {
public:
CmdReplSetFresh() : ReplSetCommand("replSetFresh") { }
private:
@@ -29,23 +29,23 @@ namespace mongo {
if( !check(errmsg, result) )
return false;
- if( cmdObj["set"].String() != theReplSet->name() ) {
+ if( cmdObj["set"].String() != theReplSet->name() ) {
errmsg = "wrong repl set name";
return false;
}
string who = cmdObj["who"].String();
int cfgver = cmdObj["cfgver"].Int();
- OpTime opTime(cmdObj["opTime"].Date());
+ OpTime opTime(cmdObj["opTime"].Date());
bool weAreFresher = false;
- if( theReplSet->config().version > cfgver ) {
+ if( theReplSet->config().version > cfgver ) {
log() << "replSet member " << who << " is not yet aware its cfg version " << cfgver << " is stale" << rsLog;
- result.append("info", "config version stale");
+ result.append("info", "config version stale");
+ weAreFresher = true;
+ }
+ else if( opTime < theReplSet->lastOpTimeWritten ) {
weAreFresher = true;
}
- else if( opTime < theReplSet->lastOpTimeWritten ) {
- weAreFresher = true;
- }
result.appendDate("opTime", theReplSet->lastOpTimeWritten.asDate());
result.append("fresher", weAreFresher);
return true;
@@ -66,19 +66,19 @@ namespace mongo {
}
} cmdReplSetElect;
- int Consensus::totalVotes() const {
+ int Consensus::totalVotes() const {
static int complain = 0;
int vTot = rs._self->config().votes;
- for( Member *m = rs.head(); m; m=m->next() )
+ for( Member *m = rs.head(); m; m=m->next() )
vTot += m->config().votes;
if( vTot % 2 == 0 && vTot && complain++ == 0 )
- log() << "replSet warning total number of votes is even - considering giving one member an extra vote" << rsLog;
+ log() << "replSet " /*buildbot! warning */ "total number of votes is even - add arbiter or give one member an extra vote" << rsLog;
return vTot;
}
bool Consensus::aMajoritySeemsToBeUp() const {
int vUp = rs._self->config().votes;
- for( Member *m = rs.head(); m; m=m->next() )
+ for( Member *m = rs.head(); m; m=m->next() )
vUp += m->hbinfo().up() ? m->config().votes : 0;
return vUp * 2 > totalVotes();
}
@@ -98,13 +98,13 @@ namespace mongo {
const time_t LeaseTime = 30;
- unsigned Consensus::yea(unsigned memberId) /* throws VoteException */ {
+ unsigned Consensus::yea(unsigned memberId) { /* throws VoteException */
Atomic<LastYea>::tran t(ly);
LastYea &ly = t.ref();
time_t now = time(0);
if( ly.when + LeaseTime >= now && ly.who != memberId ) {
log(1) << "replSet not voting yea for " << memberId <<
- " voted for " << ly.who << ' ' << now-ly.when << " secs ago" << rsLog;
+ " voted for " << ly.who << ' ' << now-ly.when << " secs ago" << rsLog;
throw VoteException();
}
ly.when = now;
@@ -112,7 +112,7 @@ namespace mongo {
return rs._self->config().votes;
}
- /* we vote for ourself at start of election. once it fails, we can cancel the lease we had in
+ /* we vote for ourself at start of election. once it fails, we can cancel the lease we had in
place instead of leaving it for a long time.
*/
void Consensus::electionFailed(unsigned meid) {
@@ -124,7 +124,7 @@ namespace mongo {
}
/* todo: threading **************** !!!!!!!!!!!!!!!! */
- void Consensus::electCmdReceived(BSONObj cmd, BSONObjBuilder* _b) {
+ void Consensus::electCmdReceived(BSONObj cmd, BSONObjBuilder* _b) {
BSONObjBuilder& b = *_b;
DEV log() << "replSet received elect msg " << cmd.toString() << rsLog;
else log(2) << "replSet received elect msg " << cmd.toString() << rsLog;
@@ -138,14 +138,14 @@ namespace mongo {
const Member* hopeful = rs.findById(whoid);
int vote = 0;
- if( set != rs.name() ) {
+ if( set != rs.name() ) {
log() << "replSet error received an elect request for '" << set << "' but our set name is '" << rs.name() << "'" << rsLog;
}
- else if( myver < cfgver ) {
+ else if( myver < cfgver ) {
// we are stale. don't vote
}
- else if( myver > cfgver ) {
+ else if( myver > cfgver ) {
// they are stale!
log() << "replSet info got stale version # during election" << rsLog;
vote = -10000;
@@ -154,10 +154,10 @@ namespace mongo {
log() << "couldn't find member with id " << whoid << rsLog;
vote = -10000;
}
- else if( primary && primary->hbinfo().opTime > hopeful->hbinfo().opTime ) {
+ else if( primary && primary->hbinfo().opTime >= hopeful->hbinfo().opTime ) {
// other members might be aware of more up-to-date nodes
log() << hopeful->fullName() << " is trying to elect itself but " <<
- primary->fullName() << " is already primary and more up-to-date" << rsLog;
+ primary->fullName() << " is already primary and more up-to-date" << rsLog;
vote = -10000;
}
else {
@@ -166,7 +166,7 @@ namespace mongo {
rs.relinquish();
log() << "replSet info voting yea for " << whoid << rsLog;
}
- catch(VoteException&) {
+ catch(VoteException&) {
log() << "replSet voting no already voted for another" << rsLog;
}
}
@@ -182,10 +182,10 @@ namespace mongo {
L.push_back( Target(m->fullName()) );
}
- /* config version is returned as it is ok to use this unlocked. BUT, if unlocked, you would need
+ /* config version is returned as it is ok to use this unlocked. BUT, if unlocked, you would need
to check later that the config didn't change. */
void ReplSetImpl::getTargets(list<Target>& L, int& configVersion) {
- if( lockedByMe() ) {
+ if( lockedByMe() ) {
_getTargets(L, configVersion);
return;
}
@@ -200,15 +200,21 @@ namespace mongo {
bool Consensus::weAreFreshest(bool& allUp, int& nTies) {
const OpTime ord = theReplSet->lastOpTimeWritten;
nTies = 0;
- assert( !ord.isNull() );
+ assert( !ord.isNull() );
BSONObj cmd = BSON(
- "replSetFresh" << 1 <<
- "set" << rs.name() <<
- "opTime" << Date_t(ord.asDate()) <<
- "who" << rs._self->fullName() <<
- "cfgver" << rs._cfg->version );
+ "replSetFresh" << 1 <<
+ "set" << rs.name() <<
+ "opTime" << Date_t(ord.asDate()) <<
+ "who" << rs._self->fullName() <<
+ "cfgver" << rs._cfg->version );
list<Target> L;
int ver;
+ /* the following queries arbiters, even though they are never fresh. wonder if that makes sense.
+ it doesn't, but it could, if they "know" what freshness it one day. so consider removing
+ arbiters from getTargets() here. although getTargets is used elsewhere for elections; there
+ arbiters are certainly targets - so a "includeArbs" bool would be necessary if we want to make
+ not fetching them herein happen.
+ */
rs.getTargets(L, ver);
multiCommand(cmd, L);
int nok = 0;
@@ -228,25 +234,25 @@ namespace mongo {
allUp = false;
}
}
- DEV log() << "replSet dev we are freshest of up nodes, nok:" << nok << " nTies:" << nTies << rsLog;
+ log(1) << "replSet dev we are freshest of up nodes, nok:" << nok << " nTies:" << nTies << rsLog;
assert( ord <= theReplSet->lastOpTimeWritten ); // <= as this may change while we are working...
return true;
}
extern time_t started;
- void Consensus::multiCommand(BSONObj cmd, list<Target>& L) {
+ void Consensus::multiCommand(BSONObj cmd, list<Target>& L) {
assert( !rs.lockedByMe() );
mongo::multiCommand(cmd, L);
}
void Consensus::_electSelf() {
- if( time(0) < steppedDown )
+ if( time(0) < steppedDown )
return;
{
const OpTime ord = theReplSet->lastOpTimeWritten;
- if( ord == 0 ) {
+ if( ord == 0 ) {
log() << "replSet info not trying to elect self, do not yet have a complete set of data from any point in time" << rsLog;
return;
}
@@ -254,16 +260,16 @@ namespace mongo {
bool allUp;
int nTies;
- if( !weAreFreshest(allUp, nTies) ) {
+ if( !weAreFreshest(allUp, nTies) ) {
log() << "replSet info not electing self, we are not freshest" << rsLog;
return;
}
rs.sethbmsg("",9);
- if( !allUp && time(0) - started < 60 * 5 ) {
- /* the idea here is that if a bunch of nodes bounce all at once, we don't want to drop data
- if we don't have to -- we'd rather be offline and wait a little longer instead
+ if( !allUp && time(0) - started < 60 * 5 ) {
+ /* the idea here is that if a bunch of nodes bounce all at once, we don't want to drop data
+ if we don't have to -- we'd rather be offline and wait a little longer instead
todo: make this configurable.
*/
rs.sethbmsg("not electing self, not all members up and we have been up less than 5 minutes");
@@ -276,9 +282,10 @@ namespace mongo {
/* tie? we then randomly sleep to try to not collide on our voting. */
/* todo: smarter. */
if( me.id() == 0 || sleptLast ) {
- // would be fine for one node not to sleep
+ // would be fine for one node not to sleep
// todo: biggest / highest priority nodes should be the ones that get to not sleep
- } else {
+ }
+ else {
assert( !rs.lockedByMe() ); // bad to go to sleep locked
unsigned ms = ((unsigned) rand()) % 1000 + 50;
DEV log() << "replSet tie " << nTies << " sleeping a little " << ms << "ms" << rsLog;
@@ -297,13 +304,13 @@ namespace mongo {
log() << "replSet info electSelf " << meid << rsLog;
BSONObj electCmd = BSON(
- "replSetElect" << 1 <<
- "set" << rs.name() <<
- "who" << me.fullName() <<
- "whoid" << me.hbinfo().id() <<
- "cfgver" << rs._cfg->version <<
- "round" << OID::gen() /* this is just for diagnostics */
- );
+ "replSetElect" << 1 <<
+ "set" << rs.name() <<
+ "who" << me.fullName() <<
+ "whoid" << me.hbinfo().id() <<
+ "cfgver" << rs._cfg->version <<
+ "round" << OID::gen() /* this is just for diagnostics */
+ );
int configVersion;
list<Target> L;
@@ -326,7 +333,7 @@ namespace mongo {
// defensive; should never happen as we have timeouts on connection and operation for our conn
log() << "replSet too much time passed during our election, ignoring result" << rsLog;
}
- else if( configVersion != rs.config().version ) {
+ else if( configVersion != rs.config().version ) {
log() << "replSet config version changed during our election, ignoring result" << rsLog;
}
else {
@@ -334,9 +341,10 @@ namespace mongo {
log(1) << "replSet election succeeded, assuming primary role" << rsLog;
success = true;
rs.assumePrimary();
- }
+ }
}
- } catch( std::exception& ) {
+ }
+ catch( std::exception& ) {
if( !success ) electionFailed(meid);
throw;
}
@@ -347,19 +355,19 @@ namespace mongo {
assert( !rs.lockedByMe() );
assert( !rs.myConfig().arbiterOnly );
assert( rs.myConfig().slaveDelay == 0 );
- try {
- _electSelf();
- }
- catch(RetryAfterSleepException&) {
+ try {
+ _electSelf();
+ }
+ catch(RetryAfterSleepException&) {
throw;
}
- catch(VoteException& ) {
+ catch(VoteException& ) {
log() << "replSet not trying to elect self as responded yea to someone else recently" << rsLog;
}
- catch(DBException& e) {
+ catch(DBException& e) {
log() << "replSet warning caught unexpected exception in electSelf() " << e.toString() << rsLog;
}
- catch(...) {
+ catch(...) {
log() << "replSet warning caught unexpected exception in electSelf()" << rsLog;
}
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-03 01:47:33 +0000