mongodb-gridfs下载文件报Sort exceeded memory limit of 104857600 bytes异常

本文主要是介绍mongodb-gridfs下载文件报Sort exceeded memory limit of 104857600 bytes异常，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

报错详细信息

com.mongodb.MongoQueryException: Query failed with error code 292 and error message 'Executor error during find command :: caused by :: Sort exceeded memory limit of 104857600 bytes, but did not opt in to external sorting.' on server 11.51.141.63:27017at com.mongodb.internal.operation.FindOperation.lambda$execute$1(FindOperation.java:670)at com.mongodb.internal.operation.OperationHelper.lambda$withSourceAndConnection$2(OperationHelper.java:564)at com.mongodb.internal.operation.OperationHelper.withSuppliedResource(OperationHelper.java:589)at com.mongodb.internal.operation.OperationHelper.lambda$withSourceAndConnection$3(OperationHelper.java:563)at com.mongodb.internal.operation.OperationHelper.withSuppliedResource(OperationHelper.java:589)at com.mongodb.internal.operation.OperationHelper.withSourceAndConnection(OperationHelper.java:562)at com.mongodb.internal.operation.FindOperation.lambda$execute$2(FindOperation.java:661)at com.mongodb.internal.async.function.RetryingSyncSupplier.get(RetryingSyncSupplier.java:65)at com.mongodb.internal.operation.FindOperation.execute(FindOperation.java:692)at com.mongodb.internal.operation.FindOperation.execute(FindOperation.java:86)at com.mongodb.client.internal.MongoClientDelegate$DelegateOperationExecutor.execute(MongoClientDelegate.java:191)at com.mongodb.client.internal.MongoIterableImpl.execute(MongoIterableImpl.java:135)at com.mongodb.client.internal.MongoIterableImpl.iterator(MongoIterableImpl.java:92)at com.mongodb.client.gridfs.GridFSDownloadStreamImpl.getCursor(GridFSDownloadStreamImpl.java:240)at com.mongodb.client.gridfs.GridFSDownloadStreamImpl.getChunk(GridFSDownloadStreamImpl.java:215)at com.mongodb.client.gridfs.GridFSDownloadStreamImpl.getBuffer(GridFSDownloadStreamImpl.java:277)at com.mongodb.client.gridfs.GridFSDownloadStreamImpl.read(GridFSDownloadStreamImpl.java:101)

解决方式（给fs.chunks集合的files_id字段加索引）如

db.fs.chunks.find();db.fs.chunks.getIndexes();
# 加索引
db.fs.chunks.createIndex({files_id: 1, n: 1}, {unique: true});

加上索引后问题得以解决！

针对网上说的

1、直接修改系统限制内存大小的变量，如

use admin
db.auth("adminuser","passwd")
db.adminCommand({setParameter:1, internalQueryExecMaxBlockingSortBytes:335544320})

执行这个命令需要admin用户认证成功，当时没有创建admin用户，也不好停掉MongoDB服务去创建admin用户，所以当时没有使用过此方式。当然不是所有的版本都有此变量，可以通过如下命令查询所有可修改的变量

db.adminCommand({getParameter: '*'})

如果查到了就可以通过以上命令修改变量值，当然如MongoDB版本是5.0以上的，也可以直接修改配置文件如

setParameter:internalQueryExecMaxBlockingSortBytes: 335544320

2、开启使用磁盘（allowDiskUse）如

db.getCollection('fs.chunks').aggregate([
{$group:{_id:"$title",count:{$sum:1},title:{$addToSet:"$title"},ids:{$addToSet:"$_id"}}},{$match:{count:{$gt:1}}}],
{allowDiskUse:true})