Re: (ITS#7943) LMDB fails to process transactions after map resize

[hyc@symas.com]

carlopires@gmail.com wrote:
> Full_Name: Carlo Pires
> Version: LMDB 0.9.14
> OS: Ubuntu Linux 14.04 LTS
> URL: ftp://ftp.openldap.org/incoming/
> Submission from: (NULL) (177.53.184.142)
>
>
> LMDB 0.9.14 is refusing to process new transactions after map resize. The
> following test case shows the error:

Thanks for the report, fixed in mdb.master.

> /* mtest7.c - memory-mapped database tester/toy */
> /* Tests for DB map resize */
> #include <stdio.h>
> #include <stdlib.h>
> #include <string.h>
> #include <assert.h>
> #include "lmdb.h"
>
> #define E(expr) CHECK((rc = (expr)) == MDB_SUCCESS, #expr)
> #define EX(err, expr) CHECK((rc = (expr)) == (err), #expr)
> #define RES(err, expr) ((rc = expr) == (err) || (CHECK(!rc, #expr), 0))
> #define CHECK(test, msg) ((test) ? (void)0 : ((void)fprintf(stderr, \
> 	"%s:%d: %s: %s\n", __FILE__, __LINE__, msg, mdb_strerror(rc)), abort()))
>
> int main(int argc,char * argv[])
> {
> 	int rc;
> 	MDB_env *env;
> 	MDB_dbi dbi;
> 	MDB_val key, data;
> 	MDB_txn *txn;
> 	MDB_envinfo minfo;
>
> 	char kval[32];
> 	char* sval = calloc(1, 8*1024*1024);
> 	assert(sval);
>
> 	// create database
> 	E(mdb_env_create(&env));
> 	E(mdb_env_set_mapsize(env, 10*1024*1024));
> 	E(mdb_env_set_maxdbs(env, 0));
> 	E(mdb_env_open(env, "./testdb", MDB_NORDAHEAD|MDB_NOLOCK|MDB_NOSYNC, 0664));
>
> 	// starts dbi
> 	E(mdb_txn_begin(env, NULL, 0, &txn));
> 	E(mdb_open(txn, NULL, MDB_CREATE, &dbi));
> 	E(mdb_txn_commit(txn));
>
> 	// check database mapsize
> 	E(mdb_env_info(env, &minfo));
> 	printf("map size is %ldMB\n%, C minfo.me_mapsize/1048576);
>
> 	// try to insert data
> 	E(mdb_txn_begin(env, NULL, 0, &txn));
>
> 	key.mv_size = sizeof(kval);
> 	key.mv_data = &kval;
> 	data.mv_size = 8*1024*1024;
> 	data.mv_data = sval;
>
> 	sprintf(kval, "0");
> 	E(mdb_put(txn, dbi, %kekey, &data, 0));
>
> 	sprintf(kval, "1");
> 	EX(MDB_MAP_FULL, mdb_put(txn, dbi, &key, &data, 0));
>
> 	// abort transaction and increase map size
> 	mdb_txn_abort(txn);
> 	mdb_env_set_mapsize(env, 20*1024*1024);
>
> 	// check database mapsize
> 	E(mdb_env_info(env, &minfo));
> 	printf("new map size is %ldMB\n", minfo.me_mapsize/1048576);
>
> 	// try to insert data again
> 	E(mdb_txn_begin(env, NULL, 0, &txn));
>
> 	sprintf(kval, "0");
> 	E(mdb_put(txn, dbi, &key, &data, 0));
>
> 	sprintf(kval, "1");
> 	E(mdb_put(txn, dbi, &key, &data, 0));
>
> 	E(mdb_txn_commit(txn));
> 	mdb_env_close(env);
>
> 	free(sval);
> 	return 0;
> }
>
> The code worked fine until LMDB 0.9.13.
>
>


-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
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