segnOutput.writeLong(siPerCommit.getFieldInfosGen());
final Map<Long,Set<String>> genUpdatesFiles = siPerCommit.getUpdatesFiles();
segnOutput.writeInt(genUpdatesFiles.size());
for (Entry<Long,Set<String>> e : genUpdatesFiles.entrySet()) {
segnOutput.writeLong(e.getKey());
segnOutput.writeStringSet(e.getValue());
}
assert si.dir == directory;
assert siPerCommit.getDelCount() <= si.getDocCount();