$ ./mongo --port 20010 --eval 'db.getSiblingDB("local").oplog.rs.stats(1024 * 1024)'
{
  "ns" : "local.oplog.rs",
  "count" : 4846273,
  "size" : 5136,
  "avgObjSize" : 1111,
  "storageSize" : 3164,
  "capped" : true,
  "max" : -1,
  "maxSize" : 5120,
  "sleepCount" : 0,
  "sleepMS" : 0,
  "wiredTiger" : {
    "metadata" : {
      "formatVersion" : 1,
      "oplogKeyExtractionVersion" : 1
    },
    "creationString" : "allocation_size=4KB,app_metadata=(formatVersion=1,oplogKeyExtractionVersion=1),block_allocation=best,block_compressor=snappy,cache_resident=0,checksum=on,colgroups=,collator=,columns=,dictionary=0,encryption=(keyid=,name=),exclusive=0,extractor=,format=btree,huffman_key=,huffman_value=,immutable=0,internal_item_max=0,internal_key_max=0,internal_key_truncate=,internal_page_max=4KB,key_format=q,key_gap=10,leaf_item_max=0,leaf_key_max=0,leaf_page_max=32KB,leaf_value_max=64MB,log=(enabled=),lsm=(auto_throttle=,bloom=,bloom_bit_count=16,bloom_config=,bloom_hash_count=8,bloom_oldest=0,chunk_count_limit=0,chunk_max=5GB,chunk_size=10MB,merge_max=15,merge_min=0),memory_page_max=10m,os_cache_dirty_max=0,os_cache_max=0,prefix_compression=0,prefix_compression_min=4,source=,split_deepen_min_child=0,split_deepen_per_child=0,split_pct=90,type=file,value_format=u",
    "type" : "file",
    "uri" : "statistics:table:collection-4--1644201538843773907",
    "LSM" : {
      "bloom filters in the LSM tree" : 0,
      "bloom filter false positives" : 0,
      "bloom filter hits" : 0,
      "bloom filter misses" : 0,
      "bloom filter pages evicted from cache" : 0,
      "bloom filter pages read into cache" : 0,
      "total size of bloom filters" : 0,
      "sleep for LSM checkpoint throttle" : 0,
      "chunks in the LSM tree" : 0,
      "highest merge generation in the LSM tree" : 0,
      "queries that could have benefited from a Bloom filter that did not exist" : 0,
      "sleep for LSM merge throttle" : 0
    },
    "block-manager" : {
      "file allocation unit size" : 4096,
      "blocks allocated" : 1619875,
      "checkpoint size" : 0,
      "allocations requiring file extension" : 116476,
      "blocks freed" : 1619842,
      "file magic number" : 120897,
      "file major version number" : 1,
      "minor version number" : 0,
      "file bytes available for reuse" : 3317309440,
      "file size in bytes" : 3318251520
    },
    "btree" : {
      "btree checkpoint generation" : 0,
      "column-store variable-size deleted values" : 0,
      "column-store fixed-size leaf pages" : 0,
      "column-store internal pages" : 0,
      "column-store variable-size RLE encoded values" : 0,
      "column-store variable-size leaf pages" : 0,
      "pages rewritten by compaction" : 0,
      "number of key/value pairs" : 0,
      "fixed-record size" : 0,
      "maximum tree depth" : 4,
      "maximum internal page key size" : 368,
      "maximum internal page size" : 4096,
      "maximum leaf page key size" : 3276,
      "maximum leaf page size" : 32768,
      "maximum leaf page value size" : 67108864,
      "overflow pages" : 0,
      "row-store internal pages" : 0,
      "row-store leaf pages" : 0
    },
    "cache" : {
      "bytes read into cache" : 12792485,
      "bytes written from cache" : 52784127588,
      "checkpoint blocked page eviction" : 0,
      "unmodified pages evicted" : 0,
      "page split during eviction deepened the tree" : 1,
      "modified pages evicted" : 24152,
      "data source pages selected for eviction unable to be evicted" : 5474,
      "hazard pointer blocked page eviction" : 947,
      "internal pages evicted" : 989,
      "internal pages split during eviction" : 10,
      "leaf pages split during eviction" : 6625,
      "in-memory page splits" : 23899,
      "in-memory page passed criteria to be split" : 69187,
      "overflow values cached in memory" : 0,
      "pages read into cache" : 393,
      "pages read into cache requiring lookaside entries" : 0,
      "overflow pages read into cache" : 0,
      "pages written from cache" : 1619875,
      "page written requiring lookaside records" : 0,
      "pages written requiring in-memory restoration" : 0
    },
    "compression" : {
      "raw compression call failed, no additional data available" : 0,
      "raw compression call failed, additional data available" : 0,
      "raw compression call succeeded" : 0,
      "compressed pages read" : 393,
      "compressed pages written" : 1618788,
      "page written failed to compress" : 723,
      "page written was too small to compress" : 364
    },
    "cursor" : {
      "create calls" : 1442,
      "insert calls" : 169121923,
      "bulk-loaded cursor-insert calls" : 0,
      "cursor-insert key and value bytes inserted" : 189478787539,
      "next calls" : 117370728,
      "prev calls" : 3,
      "remove calls" : 3400,
      "cursor-remove key bytes removed" : 30600,
      "reset calls" : 169128727,
      "restarted searches" : 1479224,
      "search calls" : 0,
      "search near calls" : 6800,
      "truncate calls" : 3400,
      "update calls" : 0,
      "cursor-update value bytes updated" : 0
    },
    "reconciliation" : {
      "dictionary matches" : 0,
      "internal page multi-block writes" : 0,
      "leaf page multi-block writes" : 6625,
      "maximum blocks required for a page" : 244,
      "internal-page overflow keys" : 0,
      "leaf-page overflow keys" : 0,
      "overflow values written" : 0,
      "pages deleted" : 17527,
      "fast-path pages deleted" : 1619482,
      "page checksum matches" : 0,
      "page reconciliation calls" : 24162,
      "page reconciliation calls for eviction" : 24162,
      "leaf page key bytes discarded using prefix compression" : 0,
      "internal page key bytes discarded using suffix compression" : 1619678
    },
    "session" : {
      "object compaction" : 0,
      "open cursor count" : 10
    },
    "transaction" : {
      "update conflicts" : 0
    }
  },
  "nindexes" : 0,
  "totalIndexSize" : 0,
  "indexSizes" : {

  },
  "ok" : 1
}