diff --git a/lib/gitlab/ci/trace/http_io.rb b/lib/gitlab/ci/trace/http_io.rb
index ac4308f4e2cbf51e15a29d6096e4626f9768758a..cff924e27ef3042ead1aa1b2f180d782adc35403 100644
--- a/lib/gitlab/ci/trace/http_io.rb
+++ b/lib/gitlab/ci/trace/http_io.rb
@@ -75,18 +75,28 @@ module Gitlab
           end
         end
 
-        def read(length = nil)
+        def read(length = nil, outbuf = "")
           out = ""
 
-          until eof? || (length && out.length >= length)
+          length ||= size - tell
+
+          until length <= 0 || eof?
             data = get_chunk
             break if data.empty?
 
-            out << data
-            @tell += data.bytesize
+            chunk_bytes = [BUFFER_SIZE - chunk_offset, length].min
+            chunk_data = data.byteslice(0, chunk_bytes)
+
+            out << chunk_data
+            @tell += chunk_data.bytesize
+            length -= chunk_data.bytesize
           end
 
-          out = out[0, length] if length && out.length > length
+          # If outbuf is passed, we put the output into the buffer. This supports IO.copy_stream functionality
+          if outbuf
+            outbuf.slice!(0, outbuf.bytesize)
+            outbuf << out
+          end
 
           out
         end
@@ -158,7 +168,7 @@ module Gitlab
             # Provider: GCS
             # - When the file size is larger than requested Content-range, the Content-range is included in responces with Net::HTTPPartialContent 206
             # - When the file size is smaller than requested Content-range, the Content-range is included in responces with Net::HTTPOK 200
-            @chunk_range ||= (chunk_start...(chunk_start + @chunk.length))
+            @chunk_range ||= (chunk_start...(chunk_start + @chunk.bytesize))
           end
 
           @chunk[chunk_offset..BUFFER_SIZE]
diff --git a/spec/controllers/projects/jobs_controller_spec.rb b/spec/controllers/projects/jobs_controller_spec.rb
index 31046c202e656429551de609c7587bf4d9d9fd4c..ba73f0251695ea02bad75ae56b6827e58d098058 100644
--- a/spec/controllers/projects/jobs_controller_spec.rb
+++ b/spec/controllers/projects/jobs_controller_spec.rb
@@ -1,7 +1,7 @@
 # coding: utf-8
 require 'spec_helper'
 
-describe Projects::JobsController do
+describe Projects::JobsController, :clean_gitlab_redis_shared_state do
   include ApiHelpers
   include HttpIOHelpers
 
@@ -10,6 +10,7 @@ describe Projects::JobsController do
   let(:user) { create(:user) }
 
   before do
+    stub_feature_flags(ci_enable_live_trace: true)
     stub_not_protect_default_branch
   end
 
diff --git a/spec/support/http_io/http_io_helpers.rb b/spec/support/http_io/http_io_helpers.rb
index 31e07e720cdfcf2e85031fc3cefa012740f9cab1..2c68c2cd9a6f959006ea7ba4c83401637008dff4 100644
--- a/spec/support/http_io/http_io_helpers.rb
+++ b/spec/support/http_io/http_io_helpers.rb
@@ -44,10 +44,11 @@ module HttpIOHelpers
 
   def remote_trace_body
     @remote_trace_body ||= File.read(expand_fixture_path('trace/sample_trace'))
+      .force_encoding(Encoding::BINARY)
   end
 
   def remote_trace_size
-    remote_trace_body.length
+    remote_trace_body.bytesize
   end
 
   def set_smaller_buffer_size_than(file_size)