Merge pull request #10171 from roliveri/azure_cache

Azure cache

gems/pending/MiqVm/miq_azure_vm.rb

@@ -1,5 +1,6 @@
 require 'MiqVm/MiqVm'
 require 'disk/modules/AzureBlobDisk'
+require 'disk/modules/miq_disk_cache'
 
 class MiqAzureVm < MiqVm
   def initialize(azure_handle, args)
@@ -57,7 +58,7 @@ def openDisks(diskFiles)
       dInfo.rawDisk = true
 
       begin
-        d = AzureBlobDisk.new(sa_svc, @uri, dInfo)
+        d = MiqDiskCache.new(AzureBlobDisk.new(sa_svc, @uri, dInfo), 100, 128)
       rescue => err
         $log.error "Couldn't open disk file: #{df}"
         $log.error err.to_s

gems/pending/disk/modules/AzureBlobDisk.rb

@@ -28,23 +28,34 @@ def d_init
 
     @storage_acct = @storage_acct_svc.accounts_by_name[@acct_name]
     raise "AzureBlob: Storage account #{@acct_name} not found." unless @storage_acct
+
+    $log.debug "AzureBlobDisk: open(#{@blob_uri})"
+    @t0 = Time.now.to_i
+    @reads = 0
+    @bytes = 0
+    @split_reads = 0
   end
 
   def d_close
+    return nil unless $log.debug?
+    t1 = Time.now.to_i
+    $log.debug "AzureBlobDisk: close(#{@blob_uri})"
+    $log.debug "AzureBlobDisk: (#{@blob_uri}) time:  #{t1 - @t0}"
+    $log.debug "AzureBlobDisk: (#{@blob_uri}) reads: #{@reads}, split_reads: #{@split_reads}"
+    $log.debug "AzureBlobDisk: (#{@blob_uri}) bytes: #{@bytes}"
     nil
   end
 
   def d_read(pos, len)
-    # puts "AzureBlobDisk#d_read(#{pos}, #{len})"
+    $log.debug "AzureBlobDisk#d_read(#{pos}, #{len})"
     return blob_read(pos, len) unless len > MAX_READ_LEN
 
+    @split_reads += 1
     ret = ""
-    bytes_read = 0
     blocks, rem = len.divmod(MAX_READ_LEN)
 
     blocks.times do
       ret << blob_read(pos, MAX_READ_LEN)
-      bytes_read += MAX_READ_LEN
     end
     ret << blob_read(pos, rem) if rem > 0
 
@@ -62,18 +73,17 @@ def d_write(_pos, _buf, _len)
   private
 
   def blob_read(start_byte, length)
+    $log.debug "AzureBlobDisk#blob_read(#{start_byte}, #{length})"
     options = {
       :start_byte => start_byte,
-      :length     => length,
-      :md5        => true
+      :length     => length
     }
     options[:date] = @snapshot if @snapshot
 
     ret = @storage_acct.get_blob_raw(@container, @blob, key, options)
 
-    content_md5  = ret.headers[:content_md5].unpack("m0").first.unpack("H*").first
-    returned_md5 = Digest::MD5.hexdigest(ret.body)
-    raise "Checksum error: #{range_str}, blob: #{@container}/#{@blob}" unless content_md5 == returned_md5
+    @reads += 1
+    @bytes += ret.body.length
 
     ret.body
   end