"compact" fails with 302: compaction halted by eviction pressure: Device or resource busy

Ops and Admin
1

Hello,

we currently have instance in Atlas and we would like to compact our storage space as we did some data cleanup after filling up the whole data storage.

We are not able to run compact command on SECONDARY nodes anymore, even when we tried to rotate nodes to PRIMARY.

After running compact command MongoDB Server restarts and prints backtrace, we are able to run compact command on other collections, which seems to be even more strange.

MongoDB Version 4.0.16

Logs:
2020-03-09T15:02:10.647+0000 I REPL [conn316] going into maintenance mode with 0 other maintenance mode tasks in progress
2020-03-09T15:02:10.647+0000 I REPL [conn316] transition to RECOVERING from SECONDARY
2020-03-09T15:02:10.647+0000 I REPL [conn316] Resetting sync source to empty, which was
2020-03-09T15:02:10.647+0000 I COMMAND [conn316] compact saleschamp.webhookRequests begin, options: paddingMode: NONE validateDocuments: 1
2020-03-09T15:02:11.334+0000 W REPL [rsBackgroundSync] Fetcher stopped querying remote oplog with error: InvalidSyncSource: sync source (config version: 1; last applied optime: { ts: Timestamp(1583766131, 1), t: 87 }; sync source index: -1; primary index: 0) is no longer valid
2020-03-09T15:02:12.948+0000 I REPL [SyncSourceFeedback] SyncSourceFeedback error sending update to app-prod-01-shard-00-00-ea5oi.mongodb.net:27017: InvalidSyncSource: Sync source was cleared. Was app-prod-01-shard-00-00-ea5oi.mongodb.net:27017
2020-03-09T15:02:13.663+0000 E STORAGE [conn316] WiredTiger error (16) [1583766133:663912][13639:0x7f24aa4dc700], WT_SESSION.compact: __compact_worker, 302: compaction halted by eviction pressure: Device or resource busy Raw: [1583766133:663912][13639:0x7f24aa4dc700], WT_SESSION.compact: __compact_worker, 302: compaction halted by eviction pressure: Device or resource busy
2020-03-09T15:02:13.663+0000 F - [conn316] Invariant failure: ret resulted in status UnknownError: 16: Device or resource busy at src/mongo/db/storage/wiredtiger/wiredtiger_record_store.cpp 1516
2020-03-09T15:02:13.664+0000 F - [conn316]

***aborting after invariant() failure


2020-03-09T15:02:13.689+0000 F -        [conn316] Got signal: 6 (Aborted).
 0x55ca8cd9c541 0x55ca8cd9b759 0x55ca8cd9bc3d 0x7f24d60735f0 0x7f24d5ccc337 0x7f24d5ccda28 0x55ca8b29e516 0x55ca8b6c095a 0x55ca8bad6698 0x55ca8b93d4bb 0x55ca8c7d88e6 0x55ca8c7df2f9 0x55ca8b3dfd6e 0x55ca8b3e1c69 0x55ca8b3e2bb1 0x55ca8b3ce85a 0x55ca8b3daf8a 0x55ca8b3d61e7 0x55ca8b3d9a01 0x55ca8c5c86f2 0x55ca8b3d43d0 0x55ca8b3d7515 0x55ca8b3d5927 0x55ca8b3d626d 0x55ca8b3d9a01 0x55ca8c5c8c55 0x55ca8ccf39d4 0x7f24d606be65 0x7f24d5d9488d
----- BEGIN BACKTRACE -----
{"backtrace":[{"b":"55CA8A84D000","o":"254F541","s":"_ZN5mongo15printStackTraceERSo"},{"b":"55CA8A84D000","o":"254E759"},{"b":"55CA8A84D000","o":"254EC3D"},{"b":"7F24D6064000","o":"F5F0"},{"b":"7F24D5C96000","o":"36337","s":"gsignal"},{"b":"7F24D5C96000","o":"37A28","s":"abort"},{"b":"55CA8A84D000","o":"A51516","s":"_ZN5mongo24invariantOKFailedWithMsgEPKcRKNS_6StatusERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES1_j"},{"b":"55CA8A84D000","o":"E7395A","s":"_ZN5mongo21WiredTigerRecordStore7compactEPNS_16OperationContextEPNS_25RecordStoreCompactAdaptorEPKNS_14CompactOptionsEPNS_12CompactStatsE"},{"b":"55CA8A84D000","o":"1289698","s":"_ZN5mongo14CollectionImpl7compactEPNS_16OperationContextEPKNS_14CompactOptionsE"},{"b":"55CA8A84D000","o":"10F04BB","s":"_ZN5mongo10CompactCmd9errmsgRunEPNS_16OperationContextERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEERKNS_7BSONObjERS8_RNS_14BSONObjBuilderE"},{"b":"55CA8A84D000","o":"1F8B8E6","s":"_ZN5mongo23ErrmsgCommandDeprecated3runEPNS_16OperationContextERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEERKNS_7BSONObjERNS_14BSONObjBuilderE"},{"b":"55CA8A84D000","o":"1F922F9","s":"_ZN5mongo12BasicCommand10Invocation3runEPNS_16OperationContextEPNS_19CommandReplyBuilderE"},{"b":"55CA8A84D000","o":"B92D6E"},{"b":"55CA8A84D000","o":"B94C69"},{"b":"55CA8A84D000","o":"B95BB1","s":"_ZN5mongo23ServiceEntryPointCommon13handleRequestEPNS_16OperationContextERKNS_7MessageERKNS0_5HooksE"},{"b":"55CA8A84D000","o":"B8185A","s":"_ZN5mongo23ServiceEntryPointMongod13handleRequestEPNS_16OperationContextERKNS_7MessageE"},{"b":"55CA8A84D000","o":"B8DF8A","s":"_ZN5mongo19ServiceStateMachine15_processMessageENS0_11ThreadGuardE"},{"b":"55CA8A84D000","o":"B891E7","s":"_ZN5mongo19ServiceStateMachine15_runNextInGuardENS0_11ThreadGuardE"},{"b":"55CA8A84D000","o":"B8CA01"},{"b":"55CA8A84D000","o":"1D7B6F2","s":"_ZN5mongo9transport26ServiceExecutorSynchronous8scheduleESt8functionIFvvEENS0_15ServiceExecutor13ScheduleFlagsENS0_23ServiceExecutorTaskNameE"},{"b":"55CA8A84D000","o":"B873D0","s":"_ZN5mongo19ServiceStateMachine22_scheduleNextWithGuardENS0_11ThreadGuardENS_9transport15ServiceExecutor13ScheduleFlagsENS2_23ServiceExecutorTaskNameENS0_9OwnershipE"},{"b":"55CA8A84D000","o":"B8A515","s":"_ZN5mongo19ServiceStateMachine15_sourceCallbackENS_6StatusE"},{"b":"55CA8A84D000","o":"B88927","s":"_ZN5mongo19ServiceStateMachine14_sourceMessageENS0_11ThreadGuardE"},{"b":"55CA8A84D000","o":"B8926D","s":"_ZN5mongo19ServiceStateMachine15_runNextInGuardENS0_11ThreadGuardE"},{"b":"55CA8A84D000","o":"B8CA01"},{"b":"55CA8A84D000","o":"1D7BC55"},{"b":"55CA8A84D000","o":"24A69D4"},{"b":"7F24D6064000","o":"7E65"},{"b":"7F24D5C96000","o":"FE88D","s":"clone"}],"processInfo":{ "mongodbVersion" : "4.0.16", "gitVersion" : "2a5433168a53044cb6b4fa8083e4cfd7ba142221", "compiledModules" : [ "enterprise" ], "uname" : { "sysname" : "Linux", "release" : "3.10.0-1062.12.1.el7.x86_64", "version" : "#1 SMP Tue Feb 4 23:02:59 UTC 2020", "machine" : "x86_64" }, "somap" : [ { "b" : "55CA8A84D000", "elfType" : 3, "buildId" : "E771748E4A839BBBD202C6EE993FAAA39DB36DAD" }, { "b" : "7FFE334E1000", "elfType" : 3, "buildId" : "4AF65CC22641CA1EF6020AAC0B8769BA121B370E" }, { "b" : "7F24D904F000", "path" : "/usr/lib64/libldap_r/libldap-2.4.so.2", "elfType" : 3, "buildId" : "E17DAD36A8A8D068135B66CFF68E2E55C0B7ECB9" }, { "b" : "7F24D8E40000", "path" : "/lib64/liblber-2.4.so.2", "elfType" : 3, "buildId" : "3192C56CD451E18EB9F29CB045432BA9C738DD29" }, { "b" : "7F24D8987000", "path" : "/lib64/libnetsnmpmibs.so.31", "elfType" : 3, "buildId" : "F81FF95F7D949F4600F793CD931E9D1AAA574A9D" }, { "b" : "7F24D8778000", "path" : "/lib64/libsensors.so.4", "elfType" : 3, "buildId" : "A2ACE3E193F25778AA87D2E221945FDCCFCF220F" }, { "b" : "7F24D8574000", "path" : "/lib64/libdl.so.2", "elfType" : 3, "buildId" : "18113E6E83D8E981B8E8D808F7F3DBB23F950A1D" }, { "b" : "7F24D830C000", "path" : "/lib64/librpm.so.3", "elfType" : 3, "buildId" : "54CE5D0D50631EC1887BC8C7BBD0B91C1A9484E9" }, { "b" : "7F24D80DF000", "path" : "/lib64/librpmio.so.3", "elfType" : 3, "buildId" : "E1EBFDA8DAE64D8A88790EDF43107FBA7E5247BA" }, { "b" : "7F24D7E70000", "path" : "/lib64/libnetsnmpagent.so.31", "elfType" : 3, "buildId" : "364D0B1B785E4EDDC1D6DC8D93560DDCB0ADB069" }, { "b" : "7F24D7C65000", "path" : "/lib64/libwrap.so.0", "elfType" : 3, "buildId" : "8C4AA46577D3AA7EBF8338BDFAECC6586EF29906" }, { "b" : "7F24D7962000", "path" : "/lib64/libnetsnmp.so.31", "elfType" : 3, "buildId" : "1B2EFF0A2F1F6B442E4CF9762FDEA5607BE3149C" }, { "b" : "7F24D76F0000", "path" : "/lib64/libssl.so.10", "elfType" : 3, "buildId" : "3B305C3BA17FE394862E749763F2956C9C890C2E" }, { "b" : "7F24D728D000", "path" : "/lib64/libcrypto.so.10", "elfType" : 3, "buildId" : "4CF1939F660008CFA869D8364651F31AACD2C1C4" }, { "b" : "7F24D7070000", "path" : "/lib64/libsasl2.so.3", "elfType" : 3, "buildId" : "E2F2017F821DD1B9D307DA1A9B8014F2941AEB7B" }, { "b" : "7F24D6E23000", "path" : "/lib64/libgssapi_krb5.so.2", "elfType" : 3, "buildId" : "E2AA8CA3D3164E7DBEC293BFA0B55D2B10DAC05D" }, { "b" : "7F24D6BB9000", "path" : "/lib64/libcurl.so.4", "elfType" : 3, "buildId" : "7C71A471444AD18F73AFAEA3EB42431A6DA96534" }, { "b" : "7F24D68B7000", "path" : "/lib64/libm.so.6", "elfType" : 3, "buildId" : "5681C054FDABCF789F4DDA66E94F1F6ED1747327" }, { "b" : "7F24D669E000", "path" : "/lib64/libresolv.so.2", "elfType" : 3, "buildId" : "3009B26B33156EAAF99787AA3DA0C6AE99649755" }, { "b" : "7F24D6496000", "path" : "/lib64/librt.so.1", "elfType" : 3, "buildId" : "4749697BF078337576C4629F0D30B296A0939779" }, { "b" : "7F24D6280000", "path" : "/lib64/libgcc_s.so.1", "elfType" : 3, "buildId" : "DAC0179F4555AEFEC9E97476201802FD20C03EC5" }, { "b" : "7F24D6064000", "path" : "/lib64/libpthread.so.0", "elfType" : 3, "buildId" : "8B33F7F8C86F8D544C63C5541A8E42B3DDFEF8B1" }, { "b" : "7F24D5C96000", "path" : "/lib64/libc.so.6", "elfType" : 3, "buildId" : "398944D32CF16A67AF51067A326E6C0CC14F90ED" }, { "b" : "7F24D92AE000", "path" : "/lib64/ld-linux-x86-64.so.2", "elfType" : 3, "buildId" : "5CC1A53B747A7E4D21198723C2B633E54F3C06D9" }, { "b" : "7F24D5A3D000", "path" : "/lib64/libssl3.so", "elfType" : 3, "buildId" : "B6321C434B5C7386B144B925CEE2798D269FDDF5" }, { "b" : "7F24D5815000", "path" : "/lib64/libsmime3.so", "elfType" : 3, "buildId" : "BDA454441F59F41D2DA36E13CEA1FC4CE95B2BBB" }, { "b" : "7F24D54E6000", "path" : "/lib64/libnss3.so", "elfType" : 3, "buildId" : "DC3B36B530F506DE4FC1A6612D7DF44D4A3DDCDB" }, { "b" : "7F24D52B6000", "path" : "/lib64/libnssutil3.so", "elfType" : 3, "buildId" : "32C8FB6C2768FFE41E0A15CBF2089A4202CA2290" }, { "b" : "7F24D50B2000", "path" : "/lib64/libplds4.so", "elfType" : 3, "buildId" : "325B8CE57A776DE0B24B362A7E0C90E903B1A4B8" }, { "b" : "7F24D4EAD000", "path" : "/lib64/libplc4.so", "elfType" : 3, "buildId" : "0460FF10A3C63749113D380C40E10DFCF066C76E" }, { "b" : "7F24D4C6F000", "path" : "/lib64/libnspr4.so", "elfType" : 3, "buildId" : "8840B019EDB66B0CFBD2F77EF196440F7928106E" }, { "b" : "7F24D48E1000", "path" : "/usr/lib64/perl5/CORE/libperl.so", "elfType" : 3, "buildId" : "E2C3C10A756404CC8888CD6CA8DFAD26064EF3CB" }, { "b" : "7F24D46C7000", "path" : "/lib64/libnsl.so.1", "elfType" : 3, "buildId" : "DD24971BA9AB317654ED2C1DCEB76BBDCDA5A6D1" }, { "b" : "7F24D4490000", "path" : "/lib64/libcrypt.so.1", "elfType" : 3, "buildId" : "84467C988F41D853C58353BEB247670E15DA8BAD" }, { "b" : "7F24D428D000", "path" : "/lib64/libutil.so.1", "elfType" : 3, "buildId" : "E0D39E293DC99997E7B4C9B6203301E6CD904B50" }, { "b" : "7F24D407D000", "path" : "/lib64/libbz2.so.1", "elfType" : 3, "buildId" : "0C85C0386F0CF41EA39969CF7F58A558D1AD3235" }, { "b" : "7F24D3E67000", "path" : "/lib64/libz.so.1", "elfType" : 3, "buildId" : "B9D5F73428BD6AD68C96986B57BEA3B7CEDB9745" }, { "b" : "7F24D3C4F000", "path" : "/lib64/libelf.so.1", "elfType" : 3, "buildId" : "F580CBEA123378EEDE9427F54758697A458411F5" }, { "b" : "7F24D3A29000", "path" : "/lib64/liblzma.so.5", "elfType" : 3, "buildId" : "3B2C97C1937B73A69C412A96D0810C43DF0C6F54" }, { "b" : "7F24D381F000", "path" : "/lib64/libpopt.so.0", "elfType" : 3, "buildId" : "7AE00165FBAF6920DD5AED6905820DDBAB589E84" }, { "b" : "7F24D35F8000", "path" : "/lib64/libselinux.so.1", "elfType" : 3, "buildId" : "D2DD4DA3FDE1477D25BFFF80F3A25FDB541A8179" }, { "b" : "7F24D33F3000", "path" : "/lib64/libcap.so.2", "elfType" : 3, "buildId" : "3BC565E0565C33B1BD37AE0070F7D8E2CE4313E4" }, { "b" : "7F24D31EA000", "path" : "/lib64/libacl.so.1", "elfType" : 3, "buildId" : "7F39882FC0B80BE53790C2EAC307D39F7DE1AD6E" }, { "b" : "7F24D2FBC000", "path" : "/lib64/liblua-5.1.so", "elfType" : 3, "buildId" : "BDD4B9CFC1D3F31D3A5A430D2F9080E020C5B0BA" }, { "b" : "7F24D2BFD000", "path" : "/lib64/libdb-5.3.so", "elfType" : 3, "buildId" : "CA8916E2C5EB6FF8582E059700E3347178823728" }, { "b" : "7F24D29D4000", "path" : "/lib64/libaudit.so.1", "elfType" : 3, "buildId" : "2E36E1B9A2D92C969E38CDDCC729F55D8BACBB2B" }, { "b" : "7F24D26EB000", "path" : "/lib64/libkrb5.so.3", "elfType" : 3, "buildId" : "3EE7267AF7BFD3B132E6A222D997DA09C96C90DD" }, { "b" : "7F24D24E7000", "path" : "/lib64/libcom_err.so.2", "elfType" : 3, "buildId" : "67E935BFABA2C914C01156B88947DD515EA51170" }, { "b" : "7F24D22B4000", "path" : "/lib64/libk5crypto.so.3", "elfType" : 3, "buildId" : "82E28CACB60C27CD6F14A6D2268F0CFF621664D0" }, { "b" : "7F24D20A4000", "path" : "/lib64/libkrb5support.so.0", "elfType" : 3, "buildId" : "4F5FBB2087BE132892467C4E7A46A3D07E5DA40B" }, { "b" : "7F24D1EA0000", "path" : "/lib64/libkeyutils.so.1", "elfType" : 3, "buildId" : "2E01D5AC08C1280D013AAB96B292AC58BC30A263" }, { "b" : "7F24D1C6D000", "path" : "/lib64/libidn.so.11", "elfType" : 3, "buildId" : "2B77BBEFFF65E94F3E0B71A4E89BEB68C4B476C5" }, { "b" : "7F24D1A40000", "path" : "/lib64/libssh2.so.1", "elfType" : 3, "buildId" : "1AF123CADB2F2910E89CBD540A06D3B33692F95E" }, { "b" : "7F24D183D000", "path" : "/lib64/libfreebl3.so", "elfType" : 3, "buildId" : "197680DAE6538245CB99723E57447C4EF2E98362" }, { "b" : "7F24D15DB000", "path" : "/lib64/libpcre.so.1", "elfType" : 3, "buildId" : "9CA3D11F018BEEB719CDB34BE800BF1641350D0A" }, { "b" : "7F24D13D6000", "path" : "/lib64/libattr.so.1", "elfType" : 3, "buildId" : "2617ECC6738047E207AE3ADD990BD6A34D11B265" }, { "b" : "7F24D11D0000", "path" : "/lib64/libcap-ng.so.0", "elfType" : 3, "buildId" : "43578677DF613E9D58128ED4AE0C344FBC1E44C0" } ] }}
 mongod(_ZN5mongo15printStackTraceERSo+0x41) [0x55ca8cd9c541]
 mongod(+0x254E759) [0x55ca8cd9b759]
 mongod(+0x254EC3D) [0x55ca8cd9bc3d]
 libpthread.so.0(+0xF5F0) [0x7f24d60735f0]
 libc.so.6(gsignal+0x37) [0x7f24d5ccc337]
 libc.so.6(abort+0x148) [0x7f24d5ccda28]
 mongod(_ZN5mongo24invariantOKFailedWithMsgEPKcRKNS_6StatusERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES1_j+0x0) [0x55ca8b29e516]
 mongod(_ZN5mongo21WiredTigerRecordStore7compactEPNS_16OperationContextEPNS_25RecordStoreCompactAdaptorEPKNS_14CompactOptionsEPNS_12CompactStatsE+0xBA) [0x55ca8b6c095a]
 mongod(_ZN5mongo14CollectionImpl7compactEPNS_16OperationContextEPKNS_14CompactOptionsE+0x1A8) [0x55ca8bad6698]
 mongod(_ZN5mongo10CompactCmd9errmsgRunEPNS_16OperationContextERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEERKNS_7BSONObjERS8_RNS_14BSONObjBuilderE+0x96B) [0x55ca8b93d4bb]
 mongod(_ZN5mongo23ErrmsgCommandDeprecated3runEPNS_16OperationContextERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEERKNS_7BSONObjERNS_14BSONObjBuilderE+0x46) [0x55ca8c7d88e6]
 mongod(_ZN5mongo12BasicCommand10Invocation3runEPNS_16OperationContextEPNS_19CommandReplyBuilderE+0xD9) [0x55ca8c7df2f9]
 mongod(+0xB92D6E) [0x55ca8b3dfd6e]
 mongod(+0xB94C69) [0x55ca8b3e1c69]
 mongod(_ZN5mongo23ServiceEntryPointCommon13handleRequestEPNS_16OperationContextERKNS_7MessageERKNS0_5HooksE+0x3D1) [0x55ca8b3e2bb1]
 mongod(_ZN5mongo23ServiceEntryPointMongod13handleRequestEPNS_16OperationContextERKNS_7MessageE+0x3A) [0x55ca8b3ce85a]
 mongod(_ZN5mongo19ServiceStateMachine15_processMessageENS0_11ThreadGuardE+0xBA) [0x55ca8b3daf8a]
 mongod(_ZN5mongo19ServiceStateMachine15_runNextInGuardENS0_11ThreadGuardE+0x97) [0x55ca8b3d61e7]
 mongod(+0xB8CA01) [0x55ca8b3d9a01]
 mongod(_ZN5mongo9transport26ServiceExecutorSynchronous8scheduleESt8functionIFvvEENS0_15ServiceExecutor13ScheduleFlagsENS0_23ServiceExecutorTaskNameE+0x1A2) [0x55ca8c5c86f2]
 mongod(_ZN5mongo19ServiceStateMachine22_scheduleNextWithGuardENS0_11ThreadGuardENS_9transport15ServiceExecutor13ScheduleFlagsENS2_23ServiceExecutorTaskNameENS0_9OwnershipE+0x150) [0x55ca8b3d43d0]
 mongod(_ZN5mongo19ServiceStateMachine15_sourceCallbackENS_6StatusE+0xB55) [0x55ca8b3d7515]
 mongod(_ZN5mongo19ServiceStateMachine14_sourceMessageENS0_11ThreadGuardE+0x357) [0x55ca8b3d5927]
 mongod(_ZN5mongo19ServiceStateMachine15_runNextInGuardENS0_11ThreadGuardE+0x11D) [0x55ca8b3d626d]
 mongod(+0xB8CA01) [0x55ca8b3d9a01]
 mongod(+0x1D7BC55) [0x55ca8c5c8c55]
 mongod(+0x24A69D4) [0x55ca8ccf39d4]
 libpthread.so.0(+0x7E65) [0x7f24d606be65]
 libc.so.6(clone+0x6D) [0x7f24d5d9488d]
-----  END BACKTRACE  -----
2020-03-09T15:02:26.364+0000 I CONTROL  [main] ***** SERVER RESTARTED *****
2

Welcome @jan,

Since this is an Atlas operational question, I suggest contacting the support team when logged into your account.

Regards,
Stennie

3

Hello @Stennie_X,

I got forwarded to the forum as regular basic support is not able to solve this issue.

4

Hi @jan,

The compaction error suggests your deployment may not have sufficient resources to complete (since the command is halted by cache eviction pressure), however the “device or resource busy” message and invariant failure seem unexpected. This is perhaps a generic message from the system I/O library, but I couldn’t find any similar problem reports of errors running compact.

Compaction may not be the best solution if you are trying to free up a significant amount of unused disk space: it is per collection and requires the secondary to go into maintenance mode (which will lead to cache pressure for a busy deployment). Compact attempts to reduce the space used by data and indexes, but effectiveness depends on the contents of the data files.

In normal usage compaction should be unnecessary as unused space within data files is marked as available for reuse by new write activity.

I got forwarded to the forum as regular basic support is not able to solve this issue.

Given you are encountering an invariant failure which causes the mongod process to abort, this is something that the support team should help you with. I’ve checked with the support team and if you can raise the issue again they’ll investigate.

I would open with a more concise description of the help needed, along the lines of:

When we try to run compact on the foo.bar collection on a secondary, the mongod process aborts with an invariant failure preceded by “compaction halted by eviction pressure: Device or resource busy”.

However, investigating the compaction error may not be the most productive approach if the underlying issue is insufficient resources.

If you want to maximise space recovery, I would recommend requesting a re-sync for secondaries with excessive preallocated storage. This is also something the support team can assist with for an Atlas cluster, using rolling maintenance to re-sync one replica set member at a time.

Regards,
Stennie

1 Like