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I always thought that traditional file systems, are geared and optimized for non-ssd drive, where, for instance, data locality is important, and fragmentation is problematic.
Is there a file system recommended today for SSD drives? Am I better off just using ext4?
If the SSD is to be your only disk platform, regardless of number of devices, then you have a quandry; how to minimize writes while maintaining reliability and performance.
More specifically, ext4, and 3 for that matter, NILFS, and almost any other modern file system will maintain a journal. Ordinarily this is desirable, however, when dealing with SSD devices it increases the writes performed against the device and thereby reduces its lifespan. One option is to select a conventional IDE, SATA, or other device to which the file system can write its journal. This way one may maintain the benefits of journaling without sacrificing lifespan of the SSD device(s). In the case of ext4 this can be accomplished as: mke2fs -O journal_dev /dev/external_device then attached to the specific file system as: mkfs.ext4 -J journal=/dev/external_device. More information can be found in the man page.
An additional feature of file systems to keep in mind when deal with SSD devices is atime. Setting atime on a file system can drastically increase the number of writes to a given device over time. Options for changing this behavior include 'relatime' and 'noatime'.
Since we seem to be focusing on ext4, the kernel documentation on the file system, including its available options, is available for reference here.
Some other options to consider: noload, as vorbote suggested, and errors=remount-ro;
Few years have passed since this question was asked and the answers were posted. It's time to post some up to date info on this topic. If anything gets outdated, please post a comment.
Since this question was specifically "Is there a file system recommended today for SSD drives?" I will focus on answering that question and post links to other relevant info.
Currently (as of December 20, 2014) the Solid State Drives article on the Arch Linux wiki recommends the following filesystems:
Btrfs is a copy-on-write filesystem for Linux released under the GPL. Its development started at Oracle in 2007. It's included in the mainline since Linux 2.6.29 (March 2009). Currently the on-disk format is stable and is not expected to change.
ext4 (fourth extended file system) is a journaling file system for Linux, started as a series of backward compatible extensions to ext3 and later developed as the successor to ext3. The official plan of development for ext4 was published as Proposal and plan for ext2/3 future development work by Theodore Ts'o on Jun 2006. It's included in the mainline since Linux 2.6.19 (November 2006) and marked as stable since Linux 2.6.28 (December, 2008).
XFS is a 64-bit journaling file system created by Silicon Graphics in 1993, default in IRIX since 5.3 (1994), ported to Linux in 2001. Currently some Linux distributions use it as a default file system. XFS has TRIM support for SSDs.
JFS is a 64-bit journaling file system created by IBM. IBM introduced JFS in AIX 3.1 in 1990. In 1999 it was released as open source and porting to Linux began. First stable version of JFS for Linux was released on June 2001. It was included in Alan Cox tree in 2.4.18pre9-ac4 and in mainline in 2.5.6 (2002). In 2012, TRIM Support was added to JFS.
You can use ext4 with the noload mount option added to your /etc/fstab file. It will make the filesystem behave as ext2 on steroids. In fact, AFAIK this is what Google uses in its data centers. You lose the safety net data journaling provides but you gain speed and longer life for your SSD.
You can make it permanent by running tune2fs -O ^has_journal on the unmounted partition(s).
