মঙ্গোডিবিতে কোন স্টোরেজ ইঞ্জিন ব্যবহার করা হয় তা জানতে আপনি স্টোরেজ ইঞ্জিন ব্যবহার করতে পারেন। সিনট্যাক্স নিম্নরূপ -
db.serverStatus().storageEngine;
স্টোরেজ ইঞ্জিনের সমস্ত কনফিগারেশন বিশদ জানতে, আপনি নিম্নলিখিত সিনট্যাক্স ব্যবহার করতে পারেন:
db.serverStatus().yourStorageEngineName;
মঙ্গোডিবি-তে কোন স্টোরেজ ইঞ্জিন ব্যবহার করা হচ্ছে তা জানতে উপরের সিনট্যাক্স বাস্তবায়ন করা যাক। প্রশ্নটি নিম্নরূপ -
> db.serverStatus().storageEngine;
নিচের আউটপুট −
{ "name" : "wiredTiger", "supportsCommittedReads" : true, "supportsSnapshotReadConcern" : true, "readOnly" : false, "persistent" : true }
উপরের স্টোরেজ ইঞ্জিন সম্পর্কে সমস্ত কনফিগারেশন বিশদ জানার জন্য, ক্যোয়ারীটি নিম্নরূপ -
> db.serverStatus().wiredTiger;
নিম্নলিখিত কনফিগারেশন বিবরণ প্রদর্শন আউটপুট -
{ "uri" : "statistics:", "LSM" : { "application work units currently queued" : 0, "merge work units currently queued" : 0, "rows merged in an LSM tree" : 0, "sleep for LSM checkpoint throttle" : 0, "sleep for LSM merge throttle" : 0, "switch work units currently queued" : 0, "tree maintenance operations discarded" : 0, "tree maintenance operations executed" : 0, "tree maintenance operations scheduled" : 0, "tree queue hit maximum" : 0 }, "async" : { "current work queue length" : 0, "maximum work queue length" : 0, "number of allocation state races" : 0, "number of flush calls" : 0, "number of operation slots viewed for allocation" : 0, "number of times operation allocation failed" : 0, "number of times worker found no work" : 0, "total allocations" : 0, "total compact calls" : 0, "total insert calls" : 0, "total remove calls" : 0, "total search calls" : 0, "total update calls" : 0 }, "block-manager" : { "blocks pre-loaded" : 173, "blocks read" : 482, "blocks written" : 312, "bytes read" : 2400256, "bytes written" : 2953216, "bytes written for checkpoint" : 2953216, "mapped blocks read" : 0, "mapped bytes read" : 0 }, "cache" : { "application threads page read from disk to cache count" : 157, "application threads page read from disk to cache time (usecs)" : 58747, "application threads page write from cache to disk count" : 172, "application threads page write from cache to disk time (usecs)" : 37010, "bytes belonging to page images in the cache" : 663718, "bytes belonging to the cache overflow table in the cache" : 182, "bytes currently in the cache" : 814060, "bytes dirty in the cache cumulative" : 2673442, "bytes not belonging to page images in the cache" : 150342, "bytes read into cache" : 614554, "bytes written from cache" : 1910375, "cache overflow cursor application thread wait time (usecs)" : 0, "cache overflow cursor internal thread wait time (usecs)" : 0, "cache overflow score" : 0, "cache overflow table entries" : 0, "cache overflow table insert calls" : 0, "cache overflow table remove calls" : 0, "checkpoint blocked page eviction" : 0, "eviction calls to get a page" : 546, "eviction calls to get a page found queue empty" : 547, "eviction calls to get a page found queue empty after locking" : 0, "eviction currently operating in aggressive mode" : 0, "eviction empty score" : 0, "eviction passes of a file" : 0, "eviction server candidate queue empty when topping up" : 0, "eviction server candidate queue not empty when topping up" : 0, "eviction server evicting pages" : 0, "eviction server slept, because we did not make progress with eviction" : 367, "eviction server unable to reach eviction goal" : 0, "eviction state" : 32, "eviction walk target pages histogram - 0-9" : 0, "eviction walk target pages histogram - 10-31" : 0, "eviction walk target pages histogram - 128 and higher" : 0, "eviction walk target pages histogram - 32-63" : 0, "eviction walk target pages histogram - 64-128" : 0, "eviction walks abandoned" : 0, "eviction walks gave up because they restarted their walk twice" : 0, "eviction walks gave up because they saw too many pages and found no candidates" : 0, "eviction walks gave up because they saw too many pages and found too few candidates" : 0, "eviction walks reached end of tree" : 0, "eviction walks started from root of tree" : 0, "eviction walks started from saved location in tree" : 0, "eviction worker thread active" : 4, "eviction worker thread created" : 0, "eviction worker thread evicting pages" : 2, "eviction worker thread removed" : 0, "eviction worker thread stable number" : 0, "failed eviction of pages that exceeded the in-memory maximum count" : 0, "failed eviction of pages that exceeded the in-memory maximum time (usecs)" : 0, "files with active eviction walks" : 0, "files with new eviction walks started" : 0, "force re-tuning of eviction workers once in a while" : 0, "hazard pointer blocked page eviction" : 0, "hazard pointer check calls" : 2, "hazard pointer check entries walked" : 0, "hazard pointer maximum array length" : 0, "in-memory page passed criteria to be split" : 0, "in-memory page splits" : 0, "internal pages evicted" : 0, "internal pages split during eviction" : 0, "leaf pages split during eviction" : 0, "maximum bytes configured" : 4803526656, "maximum page size at eviction" : 0, "modified pages evicted" : 2, "modified pages evicted by application threads" : 0, "operations timed out waiting for space in cache" : 0, "overflow pages read into cache" : 0, "page split during eviction deepened the tree" : 0, "page written requiring cache overflow records" : 0, "pages currently held in the cache" : 349, "pages evicted because they exceeded the in-memory maximum count" : 0, "pages evicted because they exceeded the in-memory maximum time (usecs)" : 0, "pages evicted because they had chains of deleted items count" : 0, "pages evicted because they had chains of deleted items time (usecs)" : 0, "pages evicted by application threads" : 0, "pages queued for eviction" : 0, "pages queued for urgent eviction" : 2, "pages queued for urgent eviction during walk" : 0, "pages read into cache" : 324, "pages read into cache after truncate" : 11, "pages read into cache after truncate in prepare state" : 0, "pages read into cache requiring cache overflow entries" : 0, "pages read into cache requiring cache overflow for checkpoint" : 0, "pages read into cache skipping older cache overflow entries" : 0, "pages read into cache with skipped cache overflow entries needed later" : 0, "pages read into cache with skipped cache overflow entries needed later by checkpoint" : 0, "pages requested from the cache" : 46897, "pages seen by eviction walk" : 0, "pages selected for eviction unable to be evicted" : 0, "pages walked for eviction" : 0, "pages written from cache" : 175, "pages written requiring in-memory restoration" : 0, "percentage overhead" : 8, "tracked bytes belonging to internal pages in the cache" : 40080, "tracked bytes belonging to leaf pages in the cache" : 773980, "tracked dirty bytes in the cache" : 0, "tracked dirty pages in the cache" : 0, "unmodified pages evicted" : 0 }, "connection" : { "auto adjusting condition resets" : 561, "auto adjusting condition wait calls" : 42647, "detected system time went backwards" : 0, "files currently open" : 170, "memory allocations" : 277416, "memory frees" : 266135, "memory re-allocations" : 23688, "pthread mutex condition wait calls" : 116127, "pthread mutex shared lock read-lock calls" : 140031, "pthread mutex shared lock write-lock calls" : 10159, "total fsync I/Os" : 760, "total read I/Os" : 2257, "total write I/Os" : 875 }, "cursor" : { "cursor close calls that result in cache" : 482, "cursor create calls" : 536, "cursor insert calls" : 296, "cursor modify calls" : 0, "cursor next calls" : 2968, "cursor operation restarted" : 0, "cursor prev calls" : 212, "cursor remove calls" : 9, "cursor reserve calls" : 0, "cursor reset calls" : 46322, "cursor search calls" : 27066, "cursor search near calls" : 441, "cursor sweep buckets" : 41532, "cursor sweep cursors closed" : 0, "cursor sweep cursors examined" : 13338, "cursor sweeps" : 6922, "cursor update calls" : 0, "cursors currently cached" : 170, "cursors reused from cache" : 312, "truncate calls" : 0 }, "data-handle" : { "connection data handles currently active" : 489, "connection sweep candidate became referenced" : 0, "connection sweep dhandles closed" : 0, "connection sweep dhandles removed from hash list" : 207, "connection sweep time-of-death sets" : 972, "connection sweeps" : 3469, "session dhandles swept" : 0, "session sweep attempts" : 373 }, "lock" : { "checkpoint lock acquisitions" : 437, "checkpoint lock application thread wait time (usecs)" : 0, "checkpoint lock internal thread wait time (usecs)" : 0, "commit timestamp queue lock application thread time waiting (usecs)" : 0, "commit timestamp queue lock internal thread time waiting (usecs)" : 0, "commit timestamp queue read lock acquisitions" : 0, "commit timestamp queue write lock acquisitions" : 0, "dhandle lock application thread time waiting (usecs)" : 0, "dhandle lock internal thread time waiting (usecs)" : 0, "dhandle read lock acquisitions" : 28619, "dhandle write lock acquisitions" : 909, "metadata lock acquisitions" : 116, "metadata lock application thread wait time (usecs)" : 0, "metadata lock internal thread wait time (usecs)" : 0, "read timestamp queue lock application thread time waiting (usecs)" : 0, "read timestamp queue lock internal thread time waiting (usecs)" : 0, "read timestamp queue read lock acquisitions" : 0, "read timestamp queue write lock acquisitions" : 0, "schema lock acquisitions" : 613, "schema lock application thread wait time (usecs)" : 0, "schema lock internal thread wait time (usecs)" : 0, "table lock application thread time waiting for the table lock (usecs)" : 0, "table lock internal thread time waiting for the table lock (usecs)" : 0, "table read lock acquisitions" : 0, "table write lock acquisitions" : 645, "txn global lock application thread time waiting (usecs)" : 0, "txn global lock internal thread time waiting (usecs)" : 0, "txn global read lock acquisitions" : 375, "txn global write lock acquisitions" : 354 }, "log" : { "busy returns attempting to switch slots" : 1, "force archive time sleeping (usecs)" : 0, "log bytes of payload data" : 49104, "log bytes written" : 105216, "log files manually zero-filled" : 0, "log flush operations" : 68872, "log force write operations" : 75951, "log force write operations skipped" : 75776, "log records compressed" : 36, "log records not compressed" : 23, "log records too small to compress" : 493, "log release advances write LSN" : 353, "log scan operations" : 4, "log scan records requiring two reads" : 3, "log server thread advances write LSN" : 175, "log server thread write LSN walk skipped" : 8776, "log sync operations" : 528, "log sync time duration (usecs)" : 29656979, "log sync_dir operations" : 1, "log sync_dir time duration (usecs)" : 0, "log write operations" : 552, "logging bytes consolidated" : 104704, "maximum log file size" : 104857600, "number of pre-allocated log files to create" : 2, "pre-allocated log files not ready and missed" : 1, "pre-allocated log files prepared" : 2, "pre-allocated log files used" : 0, "records processed by log scan" : 636, "slot close lost race" : 0, "slot close unbuffered waits" : 0, "slot closures" : 528, "slot join atomic update races" : 0, "slot join calls atomic updates raced" : 0, "slot join calls did not yield" : 552, "slot join calls found active slot closed" : 0, "slot join calls slept" : 0, "slot join calls yielded" : 0, "slot join found active slot closed" : 0, "slot joins yield time (usecs)" : 0, "slot transitions unable to find free slot" : 0, "slot unbuffered writes" : 0, "total in-memory size of compressed records" : 79123, "total log buffer size" : 33554432, "total size of compressed records" : 33250, "written slots coalesced" : 0, "yields waiting for previous log file close" : 0 }, "perf" : { "file system read latency histogram (bucket 1) - 10-49ms" : 5, "file system read latency histogram (bucket 2) - 50-99ms" : 0, "file system read latency histogram (bucket 3) - 100-249ms" : 0, "file system read latency histogram (bucket 4) - 250-499ms" : 0, "file system read latency histogram (bucket 5) - 500-999ms" : 0, "file system read latency histogram (bucket 6) - 1000ms+" : 0, "file system write latency histogram (bucket 1) - 10-49ms" : 9, "file system write latency histogram (bucket 2) - 50-99ms" : 0, "file system write latency histogram (bucket 3) - 100-249ms" : 0, "file system write latency histogram (bucket 4) - 250-499ms" : 0, "file system write latency histogram (bucket 5) - 500-999ms" : 0, "file system write latency histogram (bucket 6) - 1000ms+" : 0, "operation read latency histogram (bucket 1) - 100-249us" : 0, "operation read latency histogram (bucket 2) - 250-499us" : 0, "operation read latency histogram (bucket 3) - 500-999us" : 44, "operation read latency histogram (bucket 4) - 1000-9999us" : 20, "operation read latency histogram (bucket 5) - 10000us+" : 2, "operation write latency histogram (bucket 1) - 100-249us" : 0, "operation write latency histogram (bucket 2) - 250-499us" : 0, "operation write latency histogram (bucket 3) - 500-999us" : 7, "operation write latency histogram (bucket 4) - 1000-9999us" : 1, "operation write latency histogram (bucket 5) - 10000us+" : 1 }, "reconciliation" : { "fast-path pages deleted" : 0, "page reconciliation calls" : 193, "page reconciliation calls for eviction" : 1, "pages deleted" : 18, "split bytes currently awaiting free" : 0, "split objects currently awaiting free" : 0 }, "session" : { "open cursor count" : 22, "open session count" : 19, "session query timestamp calls" : 0, "table alter failed calls" : 0, "table alter successful calls" : 321, "table alter unchanged and skipped" : 963, "table compact failed calls" : 0, "table compact successful calls" : 0, "table create failed calls" : 0, "table create successful calls" : 7, "table drop failed calls" : 0, "table drop successful calls" : 0, "table rebalance failed calls" : 0, "table rebalance successful calls" : 0, "table rename failed calls" : 0, "table rename successful calls" : 0, "table salvage failed calls" : 0, "table salvage successful calls" : 0, "table truncate failed calls" : 0, "table truncate successful calls" : 0, "table verify failed calls" : 0, "table verify successful calls" : 0 }, "thread-state" : { "active filesystem fsync calls" : 0, "active filesystem read calls" : 0, "active filesystem write calls" : 0 }, "thread-yield" : { "application thread time evicting (usecs)" : 0, "application thread time waiting for cache (usecs)" : 0, "connection close blocked waiting for transaction state stabilization" : 0, "connection close yielded for lsm manager shutdown" : 0, "data handle lock yielded" : 0, "get reference for page index and slot time sleeping (usecs)" : 0, "log server sync yielded for log write" : 0, "page access yielded due to prepare state change" : 0, "page acquire busy blocked" : 0, "page acquire eviction blocked" : 0, "page acquire locked blocked" : 0, "page acquire read blocked" : 0, "page acquire time sleeping (usecs)" : 0, "page delete rollback time sleeping for state change (usecs)" : 0, "page reconciliation yielded due to child modification" : 0 }, "transaction" : { "Number of prepared updates" : 0, "Number of prepared updates added to cache overflow" : 0, "Number of prepared updates resolved" : 0, "commit timestamp queue entries walked" : 0, "commit timestamp queue insert to empty" : 0, "commit timestamp queue inserts to head" : 0, "commit timestamp queue inserts total" : 0, "commit timestamp queue length" : 0, "number of named snapshots created" : 0, "number of named snapshots dropped" : 0, "prepared transactions" : 0, "prepared transactions committed" : 0, "prepared transactions currently active" : 0, "prepared transactions rolled back" : 0, "query timestamp calls" : 1, "read timestamp queue entries walked" : 0, "read timestamp queue insert to empty" : 0, "read timestamp queue inserts to head" : 0, "read timestamp queue inserts total" : 0, "read timestamp queue length" : 0, "rollback to stable calls" : 0, "rollback to stable updates aborted" : 0, "rollback to stable updates removed from cache overflow" : 0, "set timestamp calls" : 0, "set timestamp commit calls" : 0, "set timestamp commit updates" : 0, "set timestamp oldest calls" : 0, "set timestamp oldest updates" : 0, "set timestamp stable calls" : 0, "set timestamp stable updates" : 0, "transaction begins" : 309, "transaction checkpoint currently running" : 0, "transaction checkpoint generation" : 117, "transaction checkpoint max time (msecs)" : 2264, "transaction checkpoint min time (msecs)" : 4, "transaction checkpoint most recent time (msecs)" : 43, "transaction checkpoint scrub dirty target" : 0, "transaction checkpoint scrub time (msecs)" : 0, "transaction checkpoint total time (msecs)" : 15771, "transaction checkpoints" : 116, "transaction checkpoints skipped because database was clean" : 0, "transaction failures due to cache overflow" : 0, "transaction fsync calls for checkpoint after allocating the transaction ID" : 116, "transaction fsync duration for checkpoint after allocating the transaction ID (usecs)" : 0, "transaction range of IDs currently pinned" : 0, "transaction range of IDs currently pinned by a checkpoint" : 0, "transaction range of IDs currently pinned by named snapshots" : 0, "transaction range of timestamps currently pinned" : 0, "transaction range of timestamps pinned by a checkpoint" : 0, "transaction range of timestamps pinned by the oldest timestamp" : 0, "transaction sync calls" : 0, "transactions committed" : 40, "transactions rolled back" : 269, "update conflicts" : 0 }, "concurrentTransactions" : { "write" : { "out" : 0, "available" : 128, "totalTickets" : 128 }, "read" : { "out" : 1, "available" : 127, "totalTickets" : 128 } } }