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LCG/gLite BDII performance measurements Lev Shamardin [email protected] Scobeltsyn Institute of Nuclear Physics, Moscow State University What is BDII really? OpenLDAP with LDBM backend Three running servers with role rotation: Lev Shamardin One is updated every minute with a set of processed ldapsearch results from any grid site. One is used to serve the requests via a port forwarding proxy One is setteling down 2 BDII users Lev Shamardin Primary users: lfc-* utilities looking for storage elements Resource Brokers updating grid information cache Some other grid utilities, but these are much less popular then the first two. 3 lfc utilities Typcal query: (GlueSEUniqueID=<se_name>) (&(GlueServiceURI=*<hostname>*) (GlueServiceType=srm_v1)) Results: Lev Shamardin Several rows for each query 4 WMS cache update Typcal query: Results: Lev Shamardin (|(objectClass=gluevoview) (|(objectClass=gluecesebind) (|(objectClass=gluece) (|(objectClass=gluecluster) (objectClass=gluesubcluster))))) Huge dump of grid resources, ~15-20 Mbytes. 5 Testing method Lev Shamardin A number of parallel quering processes, with synchronized start. Each process runs a number of query sets in a random sequence. Results from each process are collected. First implementation in perl using Net::LDAP appeared to be amazingly slow and memoryhungry, so written in C with openldap-client 6 SE search queries There is almost no dependence of the response time from the number of sequential queries Lev Shamardin 7 SE search queries (2) Lev Shamardin 8 SE search queries (3) Lev Shamardin 9 WMS queries Lev Shamardin 10 WMS queries (2) Lev Shamardin 11 Conclusion Lev Shamardin Seems to scale linearly. Just throw in more CPUs? High loads cause connection timeouts, but our test show that „high load“ for a production BDII means >1000 simulteneous queries! Protocol and implementation are quite inefficient. Network delay for the transfer of WMS dump data is ~2 sec, so could be the response time for the sequential same queries. 12 Conclusion (2) Numbers for the modeling (next talk). Net::LDAP is very slow. Lev Shamardin 13 Acknowledgements Lev Shamardin The research was partially supported by INTAS-CERN Grant 2005-7509 RFBR Grant 06-07-89199 14