diff --git a/roles/emit-job-header/README.rst b/roles/emit-job-header/README.rst
index bdb97c7ed..b67d66b62 100644
--- a/roles/emit-job-header/README.rst
+++ b/roles/emit-job-header/README.rst
@@ -5,3 +5,13 @@ Log a few lines about the job.
 .. zuul:rolevar:: zuul_log_url
 
    Base URL where logs are to be found.
+
+.. zuul:rolevar:: zuul_log_path_shard_build
+   :default: False
+
+   This var is consumed by set-zuul-log-path-fact which emit-job-header
+   calls into. If you set this you will get log paths prefixed with the
+   first three characters of the build uuid. This will improve log file
+   sharding.
+
+   More details can be found at :zuul:rolevar:`set-zuul-log-path-fact.zuul_log_path_shard_build`
diff --git a/roles/set-zuul-log-path-fact/README.rst b/roles/set-zuul-log-path-fact/README.rst
index d64eec8af..33a36d1da 100644
--- a/roles/set-zuul-log-path-fact/README.rst
+++ b/roles/set-zuul-log-path-fact/README.rst
@@ -1 +1,12 @@
 Sets a fact named ``zuul_log_path`` from zuul variables
+
+**Role Variables**
+
+.. zuul:rolevar:: zuul_log_path_shard_build
+   :type: bool
+   :default: False
+
+   Flag to specify whether or not paths that include a three character
+   prefix based on the build uuid should prefix the log path. This is
+   particularly useful for object storage systems where we want to
+   spread out the number of files per container.
diff --git a/roles/set-zuul-log-path-fact/defaults/main.yaml b/roles/set-zuul-log-path-fact/defaults/main.yaml
new file mode 100644
index 000000000..b1abb3a6f
--- /dev/null
+++ b/roles/set-zuul-log-path-fact/defaults/main.yaml
@@ -0,0 +1 @@
+zuul_log_path_shard_build: false
diff --git a/roles/set-zuul-log-path-fact/tasks/main.yaml b/roles/set-zuul-log-path-fact/tasks/main.yaml
index c49c3a85e..f9dff1b5a 100644
--- a/roles/set-zuul-log-path-fact/tasks/main.yaml
+++ b/roles/set-zuul-log-path-fact/tasks/main.yaml
@@ -1,14 +1,35 @@
-- name: Set log path for a change
-  when: zuul.change is defined
-  set_fact:
-    zuul_log_path: "{{ zuul.change[-2:] }}/{{ zuul.change }}/{{ zuul.patchset }}/{{ zuul.pipeline }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
+- name: Fileserver friendly log path specifications
+  when: not zuul_log_path_shard_build
+  block:
+    - name: Set log path for a change
+      when: zuul.change is defined
+      set_fact:
+        zuul_log_path: "{{ zuul.change[-2:] }}/{{ zuul.change }}/{{ zuul.patchset }}/{{ zuul.pipeline }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
 
-- name: Set log path for a ref update
-  when: zuul.newrev is defined
-  set_fact:
-    zuul_log_path: "{{ zuul.newrev[:2] }}/{{ zuul.newrev }}/{{ zuul.pipeline }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
+    - name: Set log path for a ref update
+      when: zuul.newrev is defined
+      set_fact:
+        zuul_log_path: "{{ zuul.newrev[:2] }}/{{ zuul.newrev }}/{{ zuul.pipeline }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
 
-- name: Set log path for a periodic job
-  when: zuul.change is not defined and zuul.newrev is not defined
-  set_fact:
-    zuul_log_path: "{{ zuul.pipeline }}/{{ zuul.project.canonical_name }}/{{ zuul.branch }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
+    - name: Set log path for a periodic job
+      when: zuul.change is not defined and zuul.newrev is not defined
+      set_fact:
+        zuul_log_path: "{{ zuul.pipeline }}/{{ zuul.project.canonical_name }}/{{ zuul.branch }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
+
+- name: object store friendly log path specifications
+  when: zuul_log_path_shard_build
+  block:
+    - name: Set log path for a change
+      when: zuul.change is defined
+      set_fact:
+        zuul_log_path: "{{ zuul.build[:3] }}/{{ zuul.change }}/{{ zuul.patchset }}/{{ zuul.pipeline }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
+
+    - name: Set log path for a ref update
+      when: zuul.newrev is defined
+      set_fact:
+        zuul_log_path: "{{ zuul.build[:3] }}/{{ zuul.newrev }}/{{ zuul.pipeline }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
+
+    - name: Set log path for a periodic job
+      when: zuul.change is not defined and zuul.newrev is not defined
+      set_fact:
+        zuul_log_path: "{{ zuul.build[:3] }}/{{ zuul.pipeline }}/{{ zuul.project.canonical_name }}/{{ zuul.branch }}/{{ zuul.job }}/{{ zuul.build[:7] }}"
diff --git a/test-playbooks/base-roles/emit-job-header.yaml b/test-playbooks/base-roles/emit-job-header.yaml
index 2dce32de2..51991e1e3 100644
--- a/test-playbooks/base-roles/emit-job-header.yaml
+++ b/test-playbooks/base-roles/emit-job-header.yaml
@@ -1,4 +1,29 @@
-- name: Test the emit-job-header role
+- name: Test the emit-job-header role with swift
+  hosts: all
+  roles:
+    - role: emit-job-header
+      zuul_log_url: "http://logs.openstack.org"
+      zuul_log_path_shard_build: true
+  post_tasks:
+    # All emit-job-header does is a debug statement so the worst that would
+    # happen would be that the debug task would fail outright and we'd prevent
+    # something breaking that debug statement from merging just by running it.
+    # However, the emit-job-header role includes the set-zuul-log-path-fact
+    # role. We can only test for zuul_log_path against changes, though.
+    - name: Assert zuul_log_path by set-zuul-log-path-fact for a change
+      assert:
+        that:
+          - zuul_log_path is defined
+          - zuul.change in zuul_log_path
+          - zuul.patchset in zuul_log_path
+          - zuul.pipeline in zuul_log_path
+          - zuul.job in zuul_log_path
+          - zuul.build[:3] == zuul_log_path[:3]
+
+# Note that the order of these two plays is important. We want the second one
+# to run to be the one the creates the correct log path for the currently
+# running system.
+- name: Test the emit-job-header role without swift
   hosts: all
   roles:
     - role: emit-job-header
@@ -17,3 +42,4 @@
           - zuul.patchset in zuul_log_path
           - zuul.pipeline in zuul_log_path
           - zuul.job in zuul_log_path
+          - zuul.build[:3] != zuul_log_path[:3]