Azure blob download is incredibly slow using PowerShell (via Get-AzureStorageBlobContent), but fast via Azure Explorer, etc? -

with basic code loops through storage account , mirrors containers , blobs local disk, i'm finding get-asurestorageblobcontent cmdlet incredibly slow? seems take real time second or 2 per blob regardless of blob size...which adds considerable overhead when we've got thousands of tiny files.

in contrast, on same machine , network connection (even running simultaneously), azure explorer same bulk copy 10x 20x faster, , azcopy literally 100x faster (async), it's not network issue.

is there more efficient way use azure storage cmdlets, or dog slow nature? get-azurestoragecontainer mentions -concurrenttaskcount option implies ability async, there's no documentation on how achieve async , given operates on single item i'm not sure how could?

this code i'm running:

$localcontent       = "c:\local_copy" $storageaccountname = "myblobaccount" $storageaccountkey  = "mykey"  import-module azure      $blob_account = new-azurestoragecontext -storageaccountname $storageaccountname -storageaccountkey $storageaccountkey -protocol https  get-azurestoragecontainer -context $blob_account | foreach-object {     $container = $_.name      get-azurestorageblob -container $container -context $blob_account | foreach-object {         $local_path = "$localcontent\{0}\{1}" -f$container,$_.name          $local_dir = split-path $local_path         if (!(test-path $local_dir)) {             new-item -path $local_dir -itemtype directory -force         }         get-azurestorageblobcontent -context $blob_account -container $container -blob $_.name -destination $local_path -force | out-null     } } 

i looked @ source code get-azurestorageblobcontent on github , found interesting things may cause slowness of downloading blobs (especially smaller sized blobs):

line 165:

icloudblob blob = channel.getblobreferencefromserver(container, blobname, accesscondition, requestoptions, operationcontext); 

what code makes request server fetch blob type. add 1 request server each blob.

line 252 - 262:

        try         {             downloadblob(blob, filepath);              channel.fetchblobattributes(blob, accesscondition, requestoptions, operationcontext);         }         catch (exception e)         {             writedebuglog(string.format(resources.downloadblobfailed, blob.name, blob.container.name, filepath, e.message));             throw;         } 

if @ code above, first downloads blob downloadblob , tries fetch blob attributes channel.fetchblobattributes. haven't looked @ source code channel.fetchblobattributes function suspect making 1 more request server.

so download single blob, code making 3 requests server reason slowness. certain, trace requests/response through fiddler , see how cmdlet interacting storage.