diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/SuggestServiceImpl.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/SuggestServiceImpl.java
index 22546a7955..7690f5cc0b 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/SuggestServiceImpl.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/rpc/SuggestServiceImpl.java
@@ -46,6 +46,7 @@ import com.google.inject.Provider;
 
 import org.eclipse.jgit.lib.Config;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.LinkedHashMap;
@@ -218,7 +219,8 @@ class SuggestServiceImpl extends BaseServiceImplementation implements
       final String query, final int limit,
       final AsyncCallback<List<ReviewerInfo>> callback) {
     run(callback, new Action<List<ReviewerInfo>>() {
-      public List<ReviewerInfo> run(final ReviewDb db) throws OrmException {
+      public List<ReviewerInfo> run(final ReviewDb db)
+          throws OrmException, Failure {
         final ChangeControl changeControl;
         try {
           changeControl = changeControlFactory.controlFor(change);
@@ -273,7 +275,7 @@ class SuggestServiceImpl extends BaseServiceImplementation implements
   }
 
   private boolean suggestGroupAsReviewer(final Project.NameKey project,
-      final GroupReference group) throws OrmException {
+      final GroupReference group) throws OrmException, Failure {
     if (!PostReviewers.isLegalReviewerGroup(group.getUUID())) {
       return false;
     }
@@ -296,6 +298,8 @@ class SuggestServiceImpl extends BaseServiceImplementation implements
       return false;
     } catch (NoSuchProjectException e) {
       return false;
+    } catch (IOException e) {
+      throw new Failure(e);
     }
 
     return true;
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java
index 08cf1a7983..2efc611e08 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/account/GroupMembers.java
@@ -28,6 +28,7 @@ import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 import com.google.inject.assistedinject.Assisted;
 
+import java.io.IOException;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.Set;
@@ -58,13 +59,13 @@ public class GroupMembers {
 
   public Set<Account> listAccounts(final AccountGroup.UUID groupUUID,
       final Project.NameKey project) throws NoSuchGroupException,
-      NoSuchProjectException, OrmException {
+      NoSuchProjectException, OrmException, IOException {
     return listAccounts(groupUUID, project, new HashSet<AccountGroup.UUID>());
   }
 
   private Set<Account> listAccounts(final AccountGroup.UUID groupUUID,
       final Project.NameKey project, final Set<AccountGroup.UUID> seen)
-      throws NoSuchGroupException, OrmException, NoSuchProjectException {
+      throws NoSuchGroupException, OrmException, NoSuchProjectException, IOException {
     if (AccountGroup.PROJECT_OWNERS.equals(groupUUID)) {
       return getProjectOwners(project, seen);
     } else {
@@ -79,7 +80,7 @@ public class GroupMembers {
 
   private Set<Account> getProjectOwners(final Project.NameKey project,
       final Set<AccountGroup.UUID> seen) throws NoSuchProjectException,
-      NoSuchGroupException, OrmException {
+      NoSuchGroupException, OrmException, IOException {
     seen.add(AccountGroup.PROJECT_OWNERS);
     if (project == null) {
       return Collections.emptySet();
@@ -100,7 +101,7 @@ public class GroupMembers {
 
   private Set<Account> getGroupMembers(final AccountGroup group,
       final Project.NameKey project, final Set<AccountGroup.UUID> seen)
-      throws NoSuchGroupException, OrmException, NoSuchProjectException {
+      throws NoSuchGroupException, OrmException, NoSuchProjectException, IOException {
     seen.add(group.getGroupUUID());
     final GroupDetail groupDetail =
         groupDetailFactory.create(group.getId()).call();
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/change/PostReviewers.java b/gerrit-server/src/main/java/com/google/gerrit/server/change/PostReviewers.java
index 70cf259d7d..59458e4031 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/change/PostReviewers.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/change/PostReviewers.java
@@ -56,6 +56,7 @@ import com.google.inject.Provider;
 
 import org.eclipse.jgit.lib.Config;
 
+import java.io.IOException;
 import java.text.MessageFormat;
 import java.util.List;
 import java.util.Set;
@@ -120,7 +121,7 @@ public class PostReviewers implements RestModifyView<ChangeResource, Input> {
   @Override
   public PostResult apply(ChangeResource rsrc, Input input)
       throws BadRequestException, ResourceNotFoundException, AuthException,
-      UnprocessableEntityException, OrmException, EmailException {
+      UnprocessableEntityException, OrmException, EmailException, IOException {
     if (input.reviewer == null) {
       throw new BadRequestException("missing reviewer field");
     }
@@ -147,8 +148,8 @@ public class PostReviewers implements RestModifyView<ChangeResource, Input> {
   }
 
   private PostResult putGroup(ChangeResource rsrc, Input input)
-      throws ResourceNotFoundException, AuthException, BadRequestException,
-      UnprocessableEntityException, OrmException, EmailException {
+      throws BadRequestException,
+      UnprocessableEntityException, OrmException, EmailException, IOException {
     GroupDescription.Basic group = groupsCollection.get().parseInternal(input.reviewer);
     PostResult result = new PostResult();
     if (!isLegalReviewerGroup(group.getGroupUUID())) {
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/project/ChangeControl.java b/gerrit-server/src/main/java/com/google/gerrit/server/project/ChangeControl.java
index f8b99759d0..d09dcb724e 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/project/ChangeControl.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/project/ChangeControl.java
@@ -42,6 +42,7 @@ import com.googlecode.prolog_cafe.lang.Term;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -71,6 +72,9 @@ public class ChangeControl {
         return projectControl.controlFor(projectKey, user).controlFor(change);
       } catch (NoSuchProjectException e) {
         throw new NoSuchChangeException(change.getId(), e);
+      } catch (IOException e) {
+        // TODO: propagate this exception
+        throw new NoSuchChangeException(change.getId(), e);
       }
     }
 
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/project/CreateProject.java b/gerrit-server/src/main/java/com/google/gerrit/server/project/CreateProject.java
index 5494146ab5..a853c75f3d 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/project/CreateProject.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/project/CreateProject.java
@@ -35,6 +35,7 @@ import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.assistedinject.Assisted;
 
+import java.io.IOException;
 import java.util.List;
 
 @RequiresCapability(GlobalCapability.CREATE_PROJECT)
@@ -79,7 +80,7 @@ class CreateProject implements RestModifyView<TopLevelResource, Input> {
   @Override
   public Object apply(TopLevelResource resource, Input input)
       throws BadRequestException, UnprocessableEntityException,
-      ProjectCreationFailedException {
+      ProjectCreationFailedException, IOException {
     if (input == null) {
       input = new Input();
     }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectControl.java b/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectControl.java
index 56d4be3b7d..3f107ec015 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectControl.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectControl.java
@@ -38,6 +38,7 @@ import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.assistedinject.Assisted;
 
+import java.io.IOException;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
@@ -62,8 +63,8 @@ public class ProjectControl {
     }
 
     public ProjectControl controlFor(Project.NameKey nameKey, CurrentUser user)
-        throws NoSuchProjectException {
-      final ProjectState p = projectCache.get(nameKey);
+        throws NoSuchProjectException, IOException {
+      final ProjectState p = projectCache.checkedGet(nameKey);
       if (p == null) {
         throw new NoSuchProjectException(nameKey);
       }
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectsCollection.java b/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectsCollection.java
index 4c00439ff1..6e9c5d9658 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectsCollection.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/project/ProjectsCollection.java
@@ -28,6 +28,8 @@ import com.google.gerrit.server.OutputFormat;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
 
+import java.io.IOException;
+
 public class ProjectsCollection implements
     RestCollection<TopLevelResource, ProjectResource>,
     AcceptsCreate<TopLevelResource> {
@@ -56,7 +58,7 @@ public class ProjectsCollection implements
 
   @Override
   public ProjectResource parse(TopLevelResource parent, IdString id)
-      throws ResourceNotFoundException {
+      throws ResourceNotFoundException, IOException {
     ProjectResource rsrc = _parse(id.get());
     if (rsrc == null) {
       throw new ResourceNotFoundException(id);
@@ -71,8 +73,10 @@ public class ProjectsCollection implements
    * @return the project
    * @throws UnprocessableEntityException thrown if the project ID cannot be
    *         resolved or if the project is not visible to the calling user
+   * @throws IOException thrown when there is an error.
    */
-  public ProjectResource parse(String id) throws UnprocessableEntityException {
+  public ProjectResource parse(String id)
+      throws UnprocessableEntityException, IOException {
     ProjectResource rsrc = _parse(id);
     if (rsrc == null) {
       throw new UnprocessableEntityException(String.format(
@@ -81,7 +85,7 @@ public class ProjectsCollection implements
     return rsrc;
   }
 
-  private ProjectResource _parse(String id) {
+  private ProjectResource _parse(String id) throws IOException {
     ProjectControl ctl;
     try {
       ctl = controlFactory.controlFor(