Message ID | 20240701132800.7158-1-jack@suse.cz |
---|---|
State | Awaiting Upstream |
Headers | show |
Series | jbd2: Increase maximum transaction size | expand |
On 2024/7/1 21:28, Jan Kara wrote: > Originally, we were quite conservative in limiting maximum transaction > size to a quarter of the journal because we were not accounting > transaction descriptor and revoke blocks. These days we do properly > account them and reserve space for them from the total transaction > credits. Thus there's no need to be so conservative and we can increase > the maximum transaction size to one third of the journal (even half > should work fine in principle but the performance will likely suffer in > that case). This also fixes failures to grow filesystems with tiny > journals. > This looks straightforward and reasonable to me. I've done some metadata intensive performance tests with fs_mark, no obvious degradation and fluctuation has been found. Reviewed-by: Zhang Yi <yi.zhang@huawei.com> Thanks, Yi. > Link: CA+hUFcuGs04JHZ_WzA1zGN57+ehL2qmHOt5a7RMpo+rv6Vyxtw@mail.gmail.com > Signed-off-by: Jan Kara <jack@suse.cz> > --- > include/linux/jbd2.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h > index ab04c1c27fae..7273ef1732bf 100644 > --- a/include/linux/jbd2.h > +++ b/include/linux/jbd2.h > @@ -1662,7 +1662,7 @@ int jbd2_fc_release_bufs(journal_t *journal); > > static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal) > { > - return (journal->j_total_len - journal->j_fc_wbufsize) / 4; > + return (journal->j_total_len - journal->j_fc_wbufsize) / 3; > } > > /* >
On Mon, 01 Jul 2024 15:28:00 +0200, Jan Kara wrote: > Originally, we were quite conservative in limiting maximum transaction > size to a quarter of the journal because we were not accounting > transaction descriptor and revoke blocks. These days we do properly > account them and reserve space for them from the total transaction > credits. Thus there's no need to be so conservative and we can increase > the maximum transaction size to one third of the journal (even half > should work fine in principle but the performance will likely suffer in > that case). This also fixes failures to grow filesystems with tiny > journals. > > [...] Applied, thanks! [1/1] jbd2: Increase maximum transaction size commit: a794c9ad026f0a28044347f31929fcdb0270eadc Best regards,
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h index ab04c1c27fae..7273ef1732bf 100644 --- a/include/linux/jbd2.h +++ b/include/linux/jbd2.h @@ -1662,7 +1662,7 @@ int jbd2_fc_release_bufs(journal_t *journal); static inline int jbd2_journal_get_max_txn_bufs(journal_t *journal) { - return (journal->j_total_len - journal->j_fc_wbufsize) / 4; + return (journal->j_total_len - journal->j_fc_wbufsize) / 3; } /*
Originally, we were quite conservative in limiting maximum transaction size to a quarter of the journal because we were not accounting transaction descriptor and revoke blocks. These days we do properly account them and reserve space for them from the total transaction credits. Thus there's no need to be so conservative and we can increase the maximum transaction size to one third of the journal (even half should work fine in principle but the performance will likely suffer in that case). This also fixes failures to grow filesystems with tiny journals. Link: CA+hUFcuGs04JHZ_WzA1zGN57+ehL2qmHOt5a7RMpo+rv6Vyxtw@mail.gmail.com Signed-off-by: Jan Kara <jack@suse.cz> --- include/linux/jbd2.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)